Compression ultrasonography for false femoral artery aneurysms: Hypocoagulability is a cause of failure

Objectives:false femoral artery aneurysm is an occasional complication of percutaneous cardiovascular radiological procedures. Compression ultrasonography causes thrombosis non-invasively, reducing need for operative intervention. The technique fails in a proportion of cases. Analysis was undertaken to identify causes of failure.Design:prospective open study.Materials and Methods:patients presenting with false femoral artery aneurysm since 1984 were identified from a computerised database (BIPAS). Since 1993 compression ultrasonography has been performed as first line treatment according to a standard protocol. Prospectively collected ultrasonographic data and case notes were reviewed to identify causes of failed compression.Results:false femoral artery aneurysm occurred as a complication in 32/26 687 (0.12%) cardiovascular radiological procedures. Eighteen aneurysms were treated by compression. The technique was successful in 11/18 (61%) cases but primary failure occurred in seven cases. Six out of seven had bleeding abnormalities (Chi-squared analysis with Yates correction 10.55, p=0.0012), four were anticoagulated and compression was subsequently successful following reversal of warfarin therapy in three of these patients. In 4/18 cases surgical repair was necessary.Conclusions:compression ultrasonography is an effective treatment of false femoral aneurysms, however, hypocoagulability is a significant cause of failure. For patients in whom anticoagulation cannot be reversed, primary surgical repair should be considered

Comment on: “Peatland carbon stocks and burn history: Blanket bog peat core evidence highlights charcoal impacts on peat physical properties and long-term carbon storage”, by A. Heinemeyer, Q. Asena, W.L. Burn and A.L. Jones (Geo: Geography and Environment. 2018; e00063)

A recent paper by Heinemeyer et al. (2018) in this journal has suggested that the use of prescribed fire may enhance carbon accumulation in UK upland blanket bogs. We challenge this finding based on a number of concerns with the original manuscript including the lack of an unburned control, insufficient replication, unrecognised potential confounding factors, and potentially large inaccuracies in the core dating approach used to calculate carbon accumulation rates. We argue that burn‐management of peatlands is more likely to lead to carbon loss than carbon gain

Application of compact laser-driven accelerator X-ray sources for industrial imaging

X-rays generated by betatron oscillations of electrons in a laser-driven plasma accelerator were characterised and applied to imaging industrial samples. With a 125TW laser, a low divergence beam with 5.2±1.7 × 107photonsmrad−2 per pulse was produced with a synchrotron spectrum with a critical energy of 14.6±1.3keV. Radiographs were obtained of a metrology test sample, battery electrodes, and a damage site in a composite material. These results demonstrate the suitability of the source for non-destructive evaluation applications. The potential for industrial implementation of plasma accelerators is discussed

Overriding water table control on managed peatland greenhouse gas emissions

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3% of all anthropogenic greenhouse gases emitted from drained peatland3–5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and rewetting of drained systems6. Here we report CO2 eddy covariance data from 16 locations and CH4 data from 41 locations in the British Isles, and combine them with published data from sites across all major peatland biomes. We find that the mean annual effective water-table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 cm of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year Global Warming Potentials) by at least 3 t CO2e ha-1 yr-1, until WTDe is < 30 cm. Raising water levels further would continue to have a net cooling effect until WTDe is < 10 cm. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1% of global anthropogenic emissions

Defra Lowland Peat 2: Managing agricultural systems on lowland peat for decreased greenhouse gas emissions whilst maintaining agricultural productivity. Report to Defra for Project SP1218

DescriptionThis report describes the results of the Defra "Lowland Peat 2" project, which ran from 2019 to 2023. This Project assessed the opportunities and challenges of managing lowland agricultural peat for reduced greenhouse gas emissions, providing evidence to support Departmental Net Zero ambitions, as well as help inform policy linked to the England Peat Action Plan (2021). Key findings include a detailed review of the opportunities and challenges for paludiculture (wetland-based agriculture) as a potential emissions mitigation measure; additional review scoping the societal impacts of lowland peat drainage, with a focus on the impacts of long-term subsidence; analyses from what is believed to be the largest network of flux towers on agricultural peatlands globally, suggesting that raising water levels could help to mitigate peat GHG emissions, and if correctly optimised may not lead to yield declines.The report also explores the role of "regenerative" farming measures in reducing peat GHGs.ObjectiveThe project assessed the opportunities and challenges of managing lowland agricultural peat for reduced greenhouse gas emissions. Primarily work in this area looks to support priorities of net zero, climate adaptation and mitigation, national food security, water security, and protection of biodiversity and habitats.. Following the earlier Lowland Peat 1 project (2014-2017) which generated fundamental data on GHG emissions from a range of contrasting lowland peat sites across England and Wales, the project focused primarily on developing and testing options to mitigate these emissions, whilst maintaining the agricultural productivity of lowland peatlands. The project coincided with a number of major peatland-related policy initiatives across the UK, including the Committee on Climate Change's 6th Carbon Budget and Net Zero Strategy, the England Peat Action Plan, and the Defra Lowland Agricultural Peat Task Force. Interim results from the project have fed into many of these initiatives, as well as to an update of emission factors for cropland and grassland on peat in the UK?s National Atmospheric Emissions Inventory

Experimental signatures of the quantum nature of radiation reaction in the field of an ultraintense laser

The motion of an electron in an external field of arbitrary intensity is one of the most fundamental outstanding problems in electrodynamics. Remarkably, there is no unanimously accepted theoretical solution for high intensities and little or no experimental data to date. The basic challenge is the inclusion of the self-interaction of the electron with the fields emitted by the electron itself -- the so-called radiation reaction (RR). As is well known, solutions exist for specific parameter ranges. At low field-strength, where RR is negligible, the equation of motion is the well-known Lorentz equation. At higher field-strength in the classical limit the Landau-Lifshitz equation is the accepted solution. For the strongest fields a full quantum description is required and this is currently the subject of active research. We report on the first experimental evidence of strong radiation reaction during the interaction of a relativistic electron beam with an intense laser field

Representational predicaments for employees: Their impact on perceptions of supervisors\u27 individualized consideration and on employee job satisfaction

A representational predicament for a subordinate vis-à-vis his or her immediate superior involves perceptual incongruence with the superior about the subordinate\u27s work or work context, with unfavourable implications for the employee. An instrument to measure the incidence of two types of representational predicament, being neglected and negative slanting, was developed and then validated through an initial survey of 327 employees. A subsequent substantive survey with a fresh sample of 330 employees largely supported a conceptual model linking being neglected and negative slanting to perceptions of low individualized consideration by superiors and to low overall job satisfaction. The respondents in both surveys were all Hong Kong Chinese. Two case examples drawn from qualitative interviews illustrate and support the conceptual model. Based on the research findings, we recommend some practical exercises to use in training interventions with leaders and subordinates. © 2013 Copyright Taylor and Francis Group, LLC

Erratum: "A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo" (2021, ApJ, 909, 218)

[no abstract available