761 research outputs found

    Basin-scale variability of microbial methanol uptake in the Atlantic Ocean

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    © 2018 Author(s). Methanol is a climate-active gas and the most abundant oxygenated volatile organic compound (OVOC) in the atmosphere and seawater. Marine methylotrophs are aerobic bacteria that utilise methanol from seawater as a source of carbon (assimilation) and/or energy (dissimilation). A few spatially limited studies have previously reported methanol oxidation rates in seawater; however, the basin-wide ubiquity of marine microbial methanol utilisation remains unknown. This study uniquely combines seawater 14C labelled methanol tracer studies with 16S rRNA pyrosequencing to investigate variability in microbial methanol dissimilation and known methanol-utilising bacteria throughout a meridional transect of the Atlantic Ocean between 47° N to 39° S. Microbial methanol dissimilation varied between 0.05 and 1.68nmolL-1h-1 in the top 200m of the Atlantic Ocean and showed significant variability between biogeochemical provinces. The highest rates of methanol dissimilation were found in the northern subtropical gyre (average 0.99±0.41nmolL-1h-1), which were up to 8 times greater than other Atlantic regions. Microbial methanol dissimilation rates displayed a significant inverse correlation with heterotrophic bacterial production (determined using 3H-leucine). Despite significant depth stratification of bacterial communities, methanol dissimilation rates showed much greater variability between oceanic provinces compared to depth. There were no significant differences in rates between samples collected under light and dark environmental conditions. The variability in the numbers of SAR11 (16S rRNA gene sequences) were estimated to explain approximately 50% of the changes in microbial methanol dissimilation rates. We estimate that SAR11 cells in the Atlantic Ocean account for between 0.3% and 59% of the rates of methanol dissimilation in Atlantic waters, compared t

    Metrology Enabled Reflection Transformation Imaging to Reconstruct Local Detail in Manufactured Surfaces

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    Understanding the performance of large high performance manufactured structures can require highly accurate dimensional measurement across large volumes with the often conflicting capability to record critical parts of the structure in fine detail. Examples include turbine blades, aircraft wings and off-site manufactured modular structures assembled on-site for city, energy and transport infrastructure. Established large-volume industrial metrology systems such as laser trackers and photogrammetry partially meet the need through the measurement of targets and reflectors, but are limited in capability to record high density local detail needed to capture the finest manufactured features. Whilst large-volume surface sensing is possible with laser radar, photogrammetric pattern projection and contact probing for example, the detail required at a local level typically demands local sensing which generally takes the form of a tracked sensor such as a triangulation laser scanner or hand held touch probe. Local sensing systems face challenges where surfaces have fine detail of similar magnitude to the local sensing system sampling capability and particularly for optical sensors where the light reflected back to the sensor by the surface includes specular reflections compounded by local geometry. This paper investigates how Reflection Transformation Imaging (RTI) with a dome camera and lighting system might be calibrated, characterised and tracked as an alternative technology that is more robust to material surface properties and capable of very fine surface detail capture. Laboratory results demonstrate the capability to characterise and locate the dome to sub-millimetric accuracy within a large-volume tracked space to achieve local surface sampling at the 30 μm × 30 μm level. A method utilising sparse touch probe points to seed conversion of low and high frequency normal maps into a common 3D surface is explored with local agreement with laser tracker surface probe check points to the order of 30 μm

    Seasonal variability in microbial methanol utilisation in coastal waters of the western English Channel

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    © The authors 2016. Methanol is ubiquitous in seawater and is the most abundant oxygenated volatile organic compound (OVOC) in the atmosphere, where it influences oxidising capacity and ozone formation. Marine methylotrophic bacteria utilise methanol in seawater as an energy and/or growth substrate. This work represents the first fully resolved seasonal study of marine microbial methanol uptake dynamics. Rates of microbial methanol dissimilation in coastal surface waters of the UK varied between 0.7 and 11.2 nmol l-1 h-1 and reached a maximum in February. Rates of microbial methanol assimilation varied between 0.04 and 2.64 10-2 nmol l-1 h-1 and reached a maximum in August. Temporal variability in microbial methanol uptake rates shows that methanol assimilation and dissimilation display opposing seasonal cycles, although overall

    Level density for deformations of the Gaussian orthogonal ensemble

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    Formulas are derived for the average level density of deformed, or transition, Gaussian orthogonal random matrix ensembles. After some general considerations about Gaussian ensembles we derive formulas for the average level density for (i) the transition from the Gaussian orthogonal ensemble (GOE) to the Poisson ensemble and (ii) the transition from the GOE to mm GOEs.Comment: 7 pages revtex4, 5 eps figures, submitted to Phys. Rev.

    Summarizing the evidence of the performance of diagnostic tests for Salmonella spp. in swine: A systematic review approach

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    A systematic review was undertaken in order to identify, critically appraise and synthesize the existing literature on the diagnostic performance (e.g. Se and Sp of the test) and agreement (e.g. kappa and correlation coefficients) of conventional bacterial culture, enzyme-linked immunosorbent assays and polymerase chain reaction assays used to detect and monitor Salmonella spp. in swine. 2110 citations were identified and 160 were relevant to the research objectives. Quality assessment is complete for 150 of these references; 73 were excluded due to estimates of test performance not being clearly reported and insufficient raw data available for post-hoc analysis. Although the review is still in progress, early experiences indicate problems with lack of standardization in the design, conduct and reporting of studies of diagnostic test evaluation in this area. This review will provide valuable information by identifying gaps in existing research and providing direction for future work on the standardization of tests examined in this review

    Explanation and Elaboration Document for the STROBE-Vet Statement: Strengthening the Reporting of Observational Studies in Epidemiology—Veterinary Extension

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    The STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement was first published in 2007 and again in 2014. The purpose of the original STROBE was to provide guidance for authors, reviewers and editors to improve the comprehensiveness of reporting; however, STROBE has a unique focus on observational studies. Although much of the guidance provided by the original STROBE document is directly applicable, it was deemed useful to map those statements to veterinary concepts, provide veterinary examples and highlight unique aspects of reporting in veterinary observational studies. Here, we present the examples and explanations for the checklist items included in the STROBE-Vet Statement. Thus, this is a companion document to the STROBE-Vet Statement Methods and process document, which describes the checklist and how it was developed

    “A Friend in the Corner”: Supporting people at home in the last year of life via telephone and video consultation – an evaluation

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    YesObjective: To evaluate a 24/7, nurse led telephone and video-consultation support service for patients thought to be in the last year of life in Bradford, Airedale, Wharfedale and Craven. Method: Activity and other data recorded at the time of calls were analysed. Interviews with 13 participants captured patients and carers perspectives. Results: Between April 1st 2014 and March 31st 2015, 4648 patients were registered on the Gold Line. 42% had a non-cancer diagnosis and 46% were not known to specialist palliative care services. The median time on the caseload was 49 days (range 1-504 days). 4533 telephone calls and 573 video consultations were received from 1813 individuals. 39% of the 5106 calls were resolved by Gold Line team without referral to other services. 69% of calls were made outside normal working hours. Interviews with patients and carers reported experiences of support and reassurance and the importance of practical advice. Conclusion: A nurse led, 24/7 telephone and video consultation service can provide valuable support for patients identified to be in the last year of life and their cares. The line enabled them to feel supported and remain in their place of residence, reducing avoidable hospital admissions and use of other services. Providing this service may encourage health care professionals to identify patients approaching the last year of life, widening support offered to this group of patients beyond those known to specialist palliative care services.Health Foundation adn Shared Purpos

    The Dudley earthquake of 22 September, 2002

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    The 4.7 ML Dudley earthquake on 22 September 2002 at 23:53 (UTC) was widely felt throughout England and Wales and was the largest earth-quake to occur onshore in the United Kingdom (UK) since the magnitude 5.1 ML Bishop's Castle earthquake in 1990. The earthquake hypocentre, determined from inversion of observed P- and S-wave travel-time data suggests a source depth of 14 km and this depth estimate is also supported by forward modelling of observed waveforms. Focal mechanisms obtained from both first motion polarites of local observations and moment tensor inversion of regional observations show left-lateral strike-slip faulting along a near vertical, near north-south striking fault plane whose orientation is in good agreement with the surface expression of the observed faults in the region. Two aftershocks were recorded within the location error ellipsoid of the mainshock. Comparison of the waveform signals revealed that the mainshock and aftershocks were nearly co-located and possibly had the same source mechanism. The observed peak ground acceleration is found to be less than that predicted using five empirical relations, which have been considered applicable in the UK. Seismic moment M0 and stress drop áşźo were measured from on-scale records where Lg arrivals were clear, and then used to give better estimates of the peak ground accelerations using a stochastic approach

    Study protocol: Reporting characteristics of intervention trials of animals published in the Journal of Dairy Science in 2017

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    Objectives The scope of this cross-sectional observational study is to evaluate prevalence of reporting the 19 objective items of the REFLECT statement checklist (Sargeant et al., 2010), with the primary outcome being prevalence of sample size calculation, in clinical trials published in the Journal of Dairy Science from January to December of 2017. We will also determine risk of bias in individual studies using the Cochrane Risk of Bias 2.0 tools for individually randomized, parallel group trials; cluster randomized, parallel group trials; and individually randomized, cross-over trials (Higgins et al., 2016)
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