762 research outputs found

    Regulation of plasmid-encoded isoprene metabolism in Rhodococcus, a representative of an important link in the global isoprene cycle

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    Emissions of biogenic volatile organic compounds (VOCs) form an important part of the global carbon cycle, comprising a significant proportion of net ecosystem productivity. They impact atmospheric chemistry and contribute directly and indirectly to greenhouse gases. Isoprene, emitted largely from plants, comprises one third of total VOCs, yet in contrast to methane, which is released in similar quantities, we know little of its biodegradation. Here, we report the genome of an isoprene degrading isolate, Rhodococcus sp. AD45, and, using mutagenesis shows that a plasmid-encoded soluble di-iron centre isoprene monooxygenase (IsoMO) is essential for isoprene metabolism. Using RNA sequencing (RNAseq) to analyse cells exposed to isoprene or epoxyisoprene in a substrate-switch time-course experiment, we show that transcripts from 22 contiguous genes, including those encoding IsoMO, were highly upregulated, becoming among the most abundant in the cell and comprising over 25% of the entire transcriptome. Analysis of gene transcription in the wild type and an IsoMO-disrupted mutant strain showed that epoxyisoprene, or a subsequent product of isoprene metabolism, rather than isoprene itself, was the inducing molecule. We provide a foundation of molecular data for future research on the environmental biological consumption of this important, climate-active compound

    Emergency intubation in trauma in KwaZuluNatal Province South Africa

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    Background. Advanced airway management is a research priority in prehospital care. There is a high burden of major trauma in KwaZulu-Natal (KZN) Province, South Africa (SA), and transfer times to trauma units are often prolonged.Objectives. To examine emergency intubation practice in trauma and burns patients in Pietermaritzburg, KZN, and its environs.Methods. This was a prospective consecutive case series, conducted from 11 May to 17 July 2016. Data were collected from urban emergency department (ED), rural hospital and roadside procedures in Pietermaritzburg and its drainage area. Patients with emergency intubation following trauma were eligible for inclusion. The primary outcome was successful airway management. Secondary outcomes included first-pass success and adverse events.Results. Forty-one cases were recorded in patients aged 1 - 60 years. No instances of unsuccessful airway management were reported. Recorded first-pass intubation success rates were higher in receiving EDs than rural hospitals (19/22 v. 2/7; p=0.003). Use of a formal preintubation checklist was associated with a higher first-pass success rate (21/23 v. 6/15; p=0.001) and fewer adverse events (0/23 v. 7/16; p<0.001). Identified adverse event rates were 1/22 (EDs), 5/8 (rural hospitals) and 2/9 (roadside). Unmedicated intubation was more common in rural hospitals than EDs (3/8 v. 1/22; p=0.019), despite absence of cardiac arrest in these cases. Minimum standards of anaesthetic monitoring were not consistently met in any setting.Conclusions. The use of a preprocedural checklist was associated with improved intubation outcomes and may improve practice in SA trauma care and the prehospital environment, including in rural hospitals. Standardised rapid sequence induction protocols, routine use of introducers and end-tidal carbon dioxide monitoring, and increased availability of intraosseous devices also merit consideration. Key performance indicators should be monitored routinely.Â

    Emergency intubation in trauma in KwaZulu-Natal Province, South Africa

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    Background. Advanced airway management is a research priority in prehospital care. There is a high burden of major trauma in KwaZulu-Natal (KZN) Province, South Africa (SA), and transfer times to trauma units are often prolonged.Objectives. To examine emergency intubation practice in trauma and burns patients in Pietermaritzburg, KZN, and its environs.Methods. This was a prospective consecutive case series, conducted from 11 May to 17 July 2016. Data were collected from urban emergency department (ED), rural hospital and roadside procedures in Pietermaritzburg and its drainage area. Patients with emergency intubation following trauma were eligible for inclusion. The primary outcome was successful airway management. Secondary outcomes included first-pass success and adverse events.Results. Forty-one cases were recorded in patients aged 1 - 60 years. No instances of unsuccessful airway management were reported. Recorded first-pass intubation success rates were higher in receiving EDs than rural hospitals (19/22 v. 2/7; p=0.003). Use of a formal preintubation checklist was associated with a higher first-pass success rate (21/23 v. 6/15; p=0.001) and fewer adverse events (0/23 v. 7/16; p<0.001). Identified adverse event rates were 1/22 (EDs), 5/8 (rural hospitals) and 2/9 (roadside). Unmedicated intubation was more common in rural hospitals than EDs (3/8 v. 1/22; p=0.019), despite absence of cardiac arrest in these cases. Minimum standards of anaesthetic monitoring were not consistently met in any setting.Conclusions. The use of a preprocedural checklist was associated with improved intubation outcomes and may improve practice in SA trauma care and the prehospital environment, including in rural hospitals. Standardised rapid sequence induction protocols, routine use of introducers and end-tidal carbon dioxide monitoring, and increased availability of intraosseous devices also merit consideration. Key performance indicators should be monitored routinely.

    Trends in suicide in Scotland 1981 – 1999: age, method and geography

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    BACKGROUND: Male suicide rates continued to increase in Scotland when rates in England and Wales declined. Female rates decreased, but at a slower rate than in England and Wales. Previous work has suggested higher than average rates in some rural areas of Scotland. This paper describes trends in suicide and undetermined death in Scotland by age, gender, geographical area and method for 1981 – 1999. METHODS: Deaths from suicide and undetermined cause in Scotland from 1981 – 1999 were identified using the records of the General Registrar Office. The deaths of people not resident in Scotland were excluded from the analysis. Death rates were calculated by area of residence, age group, gender, and method. Standardised Mortality Ratios (SMRs) and 95% confidence intervals were calculated for rates by geographical area. RESULTS: Male rates of death by suicide and undetermined death increased by 35% between 1981 – 1985 and 1996 – 1999. The largest increases were in the youngest age groups. All age female rates decreased by 7% in the same period, although there were increases in younger female age groups. The commonest methods of suicide in men were hanging, self-poisoning and car exhaust fumes. Hanging in males increased by 96.8% from 45 per million to 89 per million, compared to a 30.7% increase for self-poisoning deaths. In females, the commonest method of suicide was self-poisoning. Female hanging death rates increased in the time period. Male SMRs for 1981 – 1999 were significantly elevated in Western Isles (SMR 138, 95% CI 112 – 171), Highland (135, CI 125 – 147), and Greater Glasgow (120, CI 115 – 125). The female SMR was significantly high only in Greater Glasgow (120, CI 112 – 128). CONCLUSION: All age suicide rates increased in men and decreased in women in Scotland in 1981 – 1999. Previous findings of higher than expected male rates in some rural areas were supported. Rates were also high in Greater Glasgow, one of the most deprived areas of Scotland. There were changes in the methods used, with an increase in hanging deaths in men, and a smaller increase in hanging in women. Altered choice of method may have contributed to the increased male deaths

    The microbiology of isoprene cycling in aquatic ecosystems

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    Isoprene (2-methyl-1,3-butadiene) is emitted in vast quantities (>500 Tg C yr-1). Most isoprene is emitted by trees, but there is still incomplete understanding of the diversity of isoprene sources. The reactivity of isoprene in the atmosphere has potential implications for both global warming and global cooling, with human health implications also arising from isopreneinduced ozone formation in urban areas. Isoprene emissions from terrestrial environments have been studied for many years, but our understanding of aquatic isoprene emissions is less complete. Several abundant phytoplankton taxa produced isoprene in the laboratory, and the relationship between chlorophyll a and isoprene production has been used to estimate emissions from marine environments. The aims of this review are to highlight the role of aquatic environments in the biological cycling of isoprene and to stimulate further study of isoprene metabolism in marine and freshwater environments. From a microbial ecology perspective, the isoprene metabolic gene cluster, first identified in Rhodococcus sp. AD45 (isoGHIJABCDEF) and subsequently found in every genome-sequenced isoprene-degrader, provides the ideal basis for molecular studies on the distribution and diversity of isoprene-degrading communities. Further investigations of isopreneemitting microbes, such as the influence of environmental factors and geographical location, must also be considered when attempting to constrain estimates of the flux of isoprene in aquatic ecosystems. We also report isoprene emission by the scleractinian coral Acropora horrida and the degradation of isoprene by the same coral holobiont, which highlights the importance of better understanding the cycling of isoprene in marine environments

    Overcoming the Challenges Associated with Image-based Mapping of Small Bodies in Preparation for the OSIRIS-REx Mission to (101955) Bennu

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    The OSIRIS-REx Asteroid Sample Return Mission is the third mission in NASA's New Frontiers Program and is the first U.S. mission to return samples from an asteroid to Earth. The most important decision ahead of the OSIRIS-REx team is the selection of a prime sample-site on the surface of asteroid (101955) Bennu. Mission success hinges on identifying a site that is safe and has regolith that can readily be ingested by the spacecraft's sampling mechanism. To inform this mission-critical decision, the surface of Bennu is mapped using the OSIRIS-REx Camera Suite and the images are used to develop several foundational data products. Acquiring the necessary inputs to these data products requires observational strategies that are defined specifically to overcome the challenges associated with mapping a small irregular body. We present these strategies in the context of assessing candidate sample-sites at Bennu according to a framework of decisions regarding the relative safety, sampleability, and scientific value across the asteroid's surface. To create data products that aid these assessments, we describe the best practices developed by the OSIRIS-REx team for image-based mapping of irregular small bodies. We emphasize the importance of using 3D shape models and the ability to work in body-fixed rectangular coordinates when dealing with planetary surfaces that cannot be uniquely addressed by body-fixed latitude and longitude.Comment: 31 pages, 10 figures, 2 table

    Trace-gas metabolic versatility of the facultative methanotroph Methylocella silvestris

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    The climate-active gas methane is generated both by biological processes and by thermogenic decomposition of fossil organic material, which forms methane and short-chain alkanes, principally ethane, propane and butane1, 2. In addition to natural sources, environments are exposed to anthropogenic inputs of all these gases from oil and gas extraction and distribution. The gases provide carbon and/or energy for a diverse range of microorganisms that can metabolize them in both anoxic3 and oxic zones. Aerobic methanotrophs, which can assimilate methane, have been considered to be entirely distinct from utilizers of short-chain alkanes, and studies of environments exposed to mixtures of methane and multi-carbon alkanes have assumed that disparate groups of microorganisms are responsible for the metabolism of these gases. Here we describe the mechanism by which a single bacterial strain, Methylocella silvestris, can use methane or propane as a carbon and energy source, documenting a methanotroph that can utilize a short-chain alkane as an alternative to methane. Furthermore, during growth on a mixture of these gases, efficient consumption of both gases occurred at the same time. Two soluble di-iron centre monooxygenase (SDIMO) gene clusters were identified and were found to be differentially expressed during bacterial growth on these gases, although both were required for efficient propane utilization. This report of a methanotroph expressing an additional SDIMO that seems to be uniquely involved in short-chain alkane metabolism suggests that such metabolic flexibility may be important in many environments where methane and short-chain alkanes co-occur

    Future challenges of occupational safety and health policy-making in the UK

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    Understanding the changing landscape of occupational safety and health (OSH) regulation and standards and its implications are of central importance for ensuring that OSH outcomes are not compromised and the needs of different types of organizations are met. It is also important for developing appropriate strategies to anticipate and deal with future challenges for OSH policy-making. This paper draws on findings from two qualitative studies with key OSH stakeholders in the UK that were conducted as part of a research programme funded the Institution of Occupational Safety & Health. The aim of the first study was to elicit the views of key stakeholders on changes in the current OSH landscape so as to understand the nature and implications of these changes. The second study explored stakeholder perspectives on how to secure the optimal OSH landscape in the UK by addressing key future challenges for OSH policy-making

    Promoting the achievement in schools of children and young people in care

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    As of March 2017, there were 72,670 children and young people in care in England. The number of looked after children has continued to increase steadily over the last eight years. Sixty per cent of these children are in care because of abuse or neglect and three-quarters are placed in foster care arrangements. Children and young people who are in or have experienced care remain one of the lowest performing groups in terms of educational outcomes. The average Attainment 8 score for children in care is 19.3 compared to 44.5 for non-looked after children and 19.3 for children in need. In 2017 there was an increase in the percentage of children in care achieving a pass in English and Mathematics from 17.4% to 17.5% and also in entering EBacc. Care leavers can experience poorer employment and health outcomes after leaving school compared to their peers. They are over-represented amongst the offender population and those who experience homelessness. However, research is emerging to show that children and young people in care can have very positive experiences of school if they are supported effectively to reach their full potential academically and socially. The purpose of this report is to share practice in local authorities (LA) from across England and Wales that is contributing to improved outcomes and school experiences for children and young people in care. The case studies were all undertaken as part of the Promoting the Achievement of Looked after Children (PALAC) programme between 2014 and 2017. This report presents an account of the programme, including the activities undertaken by the participants and the outcomes of the programme to date for pupils in care and staff in the participating virtual schools (VS) and local authorities

    A four-helix bundle stores copper for methane oxidation

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    Methane-oxidising bacteria (methanotrophs) require large quantities of copper for the membrane-bound (particulate) methane monooxygenase (pMMO). Certain methanotrophs are also able to switch to using the iron-containing soluble MMO (sMMO) to catalyse methane oxidation, with this switchover regulated by copper. MMOs are Nature’s primary biological mechanism for suppressing atmospheric levels of methane, a potent greenhouse gas. Furthermore, methanotrophs and MMOs have enormous potential in bioremediation and for biotransformations producing bulk and fine chemicals, and in bioenergy, particularly considering increased methane availability from renewable sources and hydraulic fracturing of shale rock. We have discovered and characterised a novel copper storage protein (Csp1) from the methanotroph Methylosinus trichosporium OB3b that is exported from the cytosol, and stores copper for pMMO. Csp1 is a tetramer of 4-helix bundles with each monomer binding up to 13 Cu(I) ions in a previously unseen manner via mainly Cys residues that point into the core of the bundle. Csp1 is the first example of a protein that stores a metal within an established protein-folding motif. This work provides a detailed insight into how methanotrophs accumulate copper for the oxidation of methane. Understanding this process is essential if the wide-ranging biotechnological applications of methanotrophs are to be realised. Cytosolic homologues of Csp1 are present in diverse bacteria thus challenging the dogma that such organisms do not use copper in this location
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