965 research outputs found

    Automated real time detection of solar wind shocks and consequences for the identification of SSC and SI events

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    Algorithms have been developed to automatically detect Earth bound shocks in the solar wind as measured by the ACE satellite. These involve simple threshold techniques and wavelet analysis. One practical application of this shock detection is that it can provide power companies with advanced warning of the potential for geomagnetically induced currents. The automatically detected shocks have been tested against published lists of known shocks and accuracy statistics are presented. Another use for automated shock detection is an aid to the preparation of lists of rapid variations: SSC and SI events. To contribute to the IAGA published list of rapid variations, as prepared by Ebro Observatory, BGS staff routinely identify, scale and classify the events recorded at the three UK magnetic observatories. This is carried out using the criteria from the Atlas of Rapid Variations (1959) and subsequent IAGA instructions. The usefulness of automated detection of solar wind shocks for this task is examined by testing these against lists of identified SSC and SI events

    Mathematical modelling of chemical agent removal by reaction with an immiscible cleanser

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    When a hazardous chemical agent has soaked into a porous medium, such as concrete, it can be difficult to neutralise. One removal method is chemical decontamination, where a cleanser is applied to react with and neutralise the agent, forming less harmful reaction products. There are often several cleansers that could be used to neutralise the same agent, so it is important to identify the cleanser features associated with fast and effective decontamination. As many cleansers are aqueous solutions while many agents are immiscible with water, the decontamination reaction often takes place at the interface between two phases. In this paper, we develop and analyse a mathematical model of a decontamination reaction between a neat agent and an immiscible cleanser solution. We assume that the reaction product is soluble in both the cleanser phase and the agent phase. At the moving boundary between the two phases, we obtain coupling conditions from mass conservation arguments and the oil–water partition coefficient of the product. We analyse our model using both asymptotic and numerical methods, and investigate how different features of a cleanser affect the time taken to remove the agent. Our results reveal the existence of two regimes characterised by different rate-limiting transport processes, and we identify the key parameters that control the removal time in each regime. In particular, we find that the oil–water partition coefficient of the reaction product is significantly more important in determining the removal time than the effective reaction rate

    What do near-term observations tell us about long-term developments in greenhouse gas emissions? A letter

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    Long-term scenarios developed by integrated assessment models are used in climate research to provide an indication of plausible long-term emissions of greenhouse gases and other radiatively active substances based on developments in the global energy system, land-use and the emissions associated with these systems The phenomena that determine these long-term developments (several decades or even centuries) are very different than those that operate on a shorter time-scales (a few years) Nevertheless, in the literature, we still often find direct comparisons between short-term observations and long-term developments that do not take into account the differing dynamics over these time scales In this letter, we discuss some of the differences between the factors that operate in the short term and those that operate in the long term We use long-term historical emissions trends to show that short-term observations are very poor indicators of long-term future emissions developments Based on this, we conclude that the performance of long-term scenarios should be evaluated against the appropriate, corresponding long-term variables and trends The research community may facilitate this by developing appropriate data sets and protocols that can be used to test the performance of long-term scenarios and the models that produce the

    An online digital archive of magnetograms from 1846 to 1987

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    The magnetic measurements from current UK observatories, together with those from their historical predecessors, provide some of the longest running continuous sets of geophysical observations in the world. A campaign to capture high quality digital images of >300,000 analogue magnetograms (front and back) was completed in 2013, with every single image now available to search, view and download from the on-line archive at www.bgs.ac.uk/data/magnetograms. In parallel with the capture of the magnetograms, the related published yearbooks were scanned and are available online as PDF documents at www.geomag.bgs.ac.uk/data_service/data/yearbooks/yearbooks.html. This work has helped to ensure that these valuable long-term data sets are not lost, irrespective of what may happen in the future to the original photographic paper records. The additional benefit of immediate worldwide access to the data contained within these historic documents has also been established. In this paper we present the BGS OpenGeoscience service, which the magnetogram image archive forms part of. We also show some results of on-going work to acquire digital data from the images and the yearbooks. We discuss past and potential future use of the data for scientific research, such as space weather studies of the magnetograms during the period of the Carrington storm and studies into the homogeneity of long term geomagnetic activity indices that are used in space climate research

    Intoxication of cattle on kikuyu grass following army worm (Spodoptera exempta) invasion

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    Clinical features and pathological and mycological findings in a field outbreak of intoxication in dairy cattle grazing kikuyu grass are reported. The outbreak followed invasion of the grass by the army worm (Spodoptera exempta). Clinical signs included drooling of saliva, depression, apparent inco-ordination, sunken eyes, ruminal distension and atony, recumbency, moderate diarrhoea and ''sham drinking''. Seventy-seven cows (64%) were clinically affected over a period of 12 days. Of these, 37 died. Necropsies performed on 4 affected cattle revealed necrosis of the epithelium of the forestomach, which was consistently more severe in the omasum. Light microscopy showed extensive necrosis of the epithelium of the forestomach with associated fibrinopurulent inflammation. The stratum spinosum and s. granulosum were selectively involved, but the s. basale was generally preserved. Electron microscopical examination of ruminal and omasal epithelium from 2 of these cattle revealed cytopathological features in the s. spinosum and s. granulosum which were consistent with stages in an acute, anoxic type of injury. Mycological examination of the pastures revealed sparse growth of a mixed fungal population, which included Myrothecium verrucaria. There was no evidence of heavy fungal infestation. Previous evidence that M. verrucaria, or other fungi, may be involved in the aetiology of kikuyu grass poisoning of cattle in New Zealand is addressed. It appears improbable that any of the fungi isolated in this investigation could have played an important role in the aetiology of this outbreak.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

    Mathematical modelling of chemical agent removal by reaction with an immiscible cleanser

    Get PDF
    When a hazardous chemical agent has soaked into a porous medium, such as concrete, it can be difficult to neutralise. One removal method is chemical decontamination, where a cleanser is applied to react with and neutralise the agent, forming less harmful reaction products. There are often several cleansers that could be used to neutralise the same agent, so it is important to identify the cleanser features associated with fast and effective decontamination. As many cleansers are aqueous solutions while many agents are immiscible with water, the decontamination reaction often takes place at the interface between two phases. In this paper, we develop and analyse a mathematical model of a decontamination reaction between a neat agent and an immiscible cleanser solution. We assume that the reaction product is soluble in both the cleanser phase and the agent phase. At the moving boundary between the two phases, we obtain coupling conditions from mass conservation arguments and the oil–water partition coefficient of the product. We analyse our model using both asymptotic and numerical methods, and investigate how different features of a cleanser affect the time taken to remove the agent. Our results reveal the existence of two regimes characterised by different rate-limiting transport processes, and we identify the key parameters that control the removal time in each regime. In particular, we find that the oil–water partition coefficient of the reaction product is significantly more important in determining the removal time than the effective reaction rate

    Balancing livestock production and wildlife conservation in and around southern Africa's transfrontier conservation areas

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    Biodiversity conservation, of which the transfrontier conservation area movement is an integral part, and more effective livestock production/trade are pivotal to future rural development in southern Africa. For that reason, it is imperative to effectively ameliorate the obstacles that have impeded progress towards the coexistence of these two sectors for more than half a century. Transboundary animal diseases, foot and mouth disease in particular, have been and continue to be the most important of these obstacles. Fortunately, new developments in international sanitary standards applicable to trade in commodities and products derived from animals are beginning to make a solution possible. However, while progress in principle has been achieved, practical implementation remains problematic for technical reasons, exacerbated by inconsistent attitudes towards acceptance of non-traditional international trade standards. This paper describes the background to this situation, progress that has been achieved in the recent past and remaining difficulties that need to be overcome to advance towards achievement of balanced rural development in southern Africa.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1865-1682hb2013ab201

    Guidelines for Perioperative Care for Liver Surgery: Enhanced Recovery After Surgery (ERAS) Society Recommendations 2022.

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    Enhanced Recovery After Surgery (ERAS) has been widely applied in liver surgery since the publication of the first ERAS guidelines in 2016. The aim of the present article was to update the ERAS guidelines in liver surgery using a modified Delphi method based on a systematic review of the literature. A systematic literature review was performed using MEDLINE/PubMed, Embase, and the Cochrane Library. A modified Delphi method including 15 international experts was used. Consensus was judged to be reached when >80% of the experts agreed on the recommended items. Recommendations were based on the Grading of Recommendations, Assessment, Development and Evaluations system. A total of 7541 manuscripts were screened, and 240 articles were finally included. Twenty-five recommendation items were elaborated. All of them obtained consensus (>80% agreement) after 3 Delphi rounds. Nine items (36%) had a high level of evidence and 16 (64%) a strong recommendation grade. Compared to the first ERAS guidelines published, 3 novel items were introduced: prehabilitation in high-risk patients, preoperative biliary drainage in cholestatic liver, and preoperative smoking and alcohol cessation at least 4 weeks before hepatectomy. These guidelines based on the best available evidence allow standardization of the perioperative management of patients undergoing liver surgery. Specific studies on hepatectomy in cirrhotic patients following an ERAS program are still needed

    International trade standards for commodities and products derived from animals : the need for a system that integrates food safety and animal disease risk management

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    A case is made for greater emphasis to be placed on value chain management as an alternative to geographically based disease risk mitigation for trade in commodities and products derived from animals. The geographic approach is dependent upon achievement of freedom in countries or zones from infectious agents that cause so-called transboundary animal diseases, while value chain-based risk management depends upon mitigation of animal disease hazards potentially associated with specific commodities or products irrespective of the locality of production. This commodity-specific approach is founded on the same principles upon which international food safety standards are based, viz. hazard analysis critical control points (HACCP). Broader acceptance of a value chain approach enables animal disease risk management to be combined with food safety management by the integration of commodity-based trade and HACCP methodologies and thereby facilitates ‘farm to fork’ quality assurance. The latter is increasingly recognized as indispensable to food safety assurance and is therefore a pre-condition to safe trade. The biological principles upon which HACCP and commodity-based trade are based are essentially identical, potentially simplifying sanitary control in contrast to current separate international sanitary standards for food safety and animal disease risks that are difficult to reconcile. A value chain approach would not only enable more effective integration of food safety and animal disease risk management of foodstuffs derived from animals but would also ameliorate adverse environmental and associated socio-economic consequences of current sanitary standards based on the geographic distribution of animal infections. This is especially the case where vast veterinary cordon fencing systems are relied upon to separate livestock and wildlife as is the case in much of southern Africa. A value chain approach would thus be particularly beneficial to under-developed regions of the world such as southern Africa specifically and sub-Saharan Africa more generally where it would reduce incompatibility between attempts to expand and commercialize livestock production and the need to conserve the subcontinent’s unparalleled wildlife and wilderness resources.US Agency for International Development (USAID) and The Rockefeller Foundationhttp://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1865-1682hb2013ab201

    Translation to practice: a randomised controlled study of an evidenced based booklet targeted at breast care nurses in the United Kingdom

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    BACKGROUND: In the United Kingdom (UK), it was documented that a problem of knowledge transfer existed within the speciality of breast-cancer care, thus depriving patients of receiving optimal care. Despite increasingly robust research evidence indicating recommendation of whole body exercise for people affected by breast cancer, commensurate changes to practice were not noted amongst breast-care nurses (BCNs). AIM: To evaluate the effect of a targeted booklet, Exercise and Breast Cancer: A Booklet for Breast-Care Nurses, on changes in knowledge, reported practice, and attitudes of BCNs in the UK. METHOD: A prospective, experimental approach was used for designing a pre- and post-test randomised controlled study. Comparisons of knowledge, reported practice, and attitudes based on responses to a questionnaire were made at two time-points in two groups of BCNs (control and experimental). The unit of randomisation and analysis was hospital clusters of BCNs. The sample comprised 92 nurses from 62 hospitals. Analysis consisted of descriptive statistics and clustered regression techniques: clustered logistic regression for knowledge items, clustered linear regression for knowledge scores, ologit for attitude and reported practice items, and clustered multiple regression for paired and multiple variable analysis. RESULTS: A statistically significant increase in knowledge and changes in reported practice and attitudes were found. Robust variables affecting knowledge acquisition were: promotion of health, promotion of exercise, and understanding how exercise can reduce cancer-related fatigue. DISCUSSION: The study has shown that evidence-based printed material, such as an information booklet, can be used as an effective research dissemination method when developed for needs, values, and context of a target audience. CONCLUSIONS: This practical approach to research dissemination could be replicated and applied to other groups of nurses.</p
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