3,716 research outputs found

    Coombs Hill: A Late Devonian fossil locality in the Witpoort Formation (Witteberg Group, South Africa)

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    Coombs Hill, a new fossil locality in the Witpoort Formation (Witteberg Group) of South Africa, preserves a record of Famennian (Late Devonian) life in Gondwana. Fossil plants collected at Coombs Hill are preliminarily assigned to several classes. Shelly invertebrates include a variety of bivalve mollusc forms, some of which appear to be preserved in life position. Biodiversity at Coombs Hill is comparable to that of the well-known Waterloo Farm lagerstätte in ordinal diversity, but exhibits differences in species composition. Ongoing taxonomic analysis will provide a rare window into the ecology of high-latitude environments during this pivotal stage of Earth history, which immediately preceded the end-Devonian extinction. Sandstone dominated sedimentary facies at Coombs Hill suggest a high-energy coastal marine setting, with brackish back-barrier estuarine/lagoonally derived fossiliferous mudstones. Exact stratigraphic placement within the Witpoort Formation is hampered by structural deformation, and precise age comparisons with Waterloo Farm are currently tenuous.Significance: A new fossil locality at Coombs Hill comprises the second known site with a suite of well preserved continental and marginal marine fossils from the Witpoort Formation, providing an exceptionally rare example of high-latitude life during the critical latest Devonian Famennian age. Several new plant taxa will be diagnosed from this locality, which also gives important insights into the morphology of Archaeopteris notosaria, South Africa’s earliest known tree. Discovery of a second palaeontologically significant site in the Witpoort Formation provides impetus for further structural and sedimentary facies analyses to align the unit with datable global eustatic events, and to clarify its internal chronology

    Seeing the body distorts tactile size perception

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    Vision of the body modulates somatosensation, even when entirely non-informative about stimulation. For example, seeing the body increases tactile spatial acuity, but reduces acute pain. While previous results demonstrate that vision of the body modulates somatosensory sensitivity, it is unknown whether vision also affects metric properties of touch, and if so how. This study investigated how non-informative vision of the body modulates tactile size perception. We used the mirror box illusion to induce the illusion that participants were directly seeing their stimulated left hand, though they actually saw their reflected right hand. We manipulated whether participants: (a) had the illusion of directly seeing their stimulated left hand, (b) had the illusion of seeing a non-body object at the same location, or (c) looked directly at their non-stimulated right-hand. Participants made verbal estimates of the perceived distance between two tactile stimuli presented simultaneously to the dorsum of the left hand, either 20, 30, or 40 mm apart. Vision of the body significantly reduced the perceived size of touch, compared to vision of the object or of the contralateral hand. In contrast, no apparent changes of perceived hand size were found. These results show that seeing the body distorts tactile size perception

    Radio Bubbles in Clusters

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    We extend our earlier work on cluster cores with distinct radio bubbles, adding more active bubbles, i.e. those with Ghz radio emission, to our sample, and also investigating ``ghost bubbles,'' i.e. those without GHz radio emission. We have determined k, which is the ratio of the total particle energy to that of the electrons radiating between 10 MHz and 10 GHz. Constraints on the ages of the active bubbles confirm that the ratio of the energy factor, k, to the volume filling factor, f lies within the range 1 < k/f < 1000. In the assumption that there is pressure equilibrium between the radio-emitting plasma and the surrounding thermal X-ray gas, none of the radio lobes has equipartition between the relativistic particles and the magnetic field. A Monte-Carlo simulation of the data led to the conclusion that there are not enough bubbles present in the current sample to be able to determine the shape of the population. An analysis of the ghost bubbles in our sample showed that on the whole they have higher upper limits on k/f than the active bubbles, especially when compared to those in the same cluster. A study of the Brightest 55 cluster sample shows that 17, possibly 20, clusters required some form of heating as they have a short central cooling time, t_cool < 3 Gyr, and a large central temperature drop, T_centre/T_outer< 1/2. Of these between 12 (70 per cent) and 15 (75 per cent), contain bubbles. This indicates that the duty cycle of bubbles is large in such clusters and that they can play a major role in the heating process.Comment: 12 pages, Accepted for publication in MNRA

    Children’s services in the age of information technology: What matters most to frontline professionals

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    Summary The last two decades have seen information systems featuring prominently in calls for the modernisation of the UK social care system. However, critics have maintained that these systems are of limited value to social care professionals whose design and implementation is driven by a preoccupation with performance management and a culture of professional audit and accountability, precepts of 'managerialism'. However, this area of research has often suffered from lack of focus on how technological changes affect public administration and service delivery and often characterises technology as a politically neutral tool detached from its socio-political context whilst also ignoring the strategic predispositions of human service professionals.Findings This research was conducted in three local authorities in England. Using the 'technological affordance' perspective, we contend that the way social workers interact with Integrated Children's System is shaped by the discord between socio-historically evolved professional values epitomising the social work profession and managerialist reforms promoting standardised ways of performing it. Application Integrated Children's System has transformed social work from an art to a technical activity, dominated by unimaginative and routinised working practices. Social workers are becoming peripheral figures and this is where social work needs to be reclaimed. Policymakers need to rethink taken for granted assumptions that practitioners would replace their professional expertise with technology and realise that the effective use of Integrated Children's System depends on bureau-professionalised judgements of social workers. Whilst specific patterns of technology usage can be developed and institutionalised, real objectives of children's social services should not be sacrificed

    Plasma phospholipid fatty acids and CHD in older men: Whitehall study of London civil servants

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    Dietary fatty acids (FA) are the major determinants of blood lipids, and measurements of plasma phospholipid FA (PL-FA) composition that reflect the dietary intake of FA may provide insights into the relationships between diet and CHD. We assessed CHD mortality associations with PL-FA (SFA, PUFA and MUFA) levels measured in a nested case-control study of 116 cases of CHD death and 239 controls that were frequency-matched for age and employment grade. The participants had plasma levels of total cholesterol, LDL-cholesterol (LDL-C), HDL-cholesterol, apo B and apo A(1), C-reactive protein (CRP) and fibrinogen recorded. SFA levels were significantly positively correlated with total cholesterol, LDL-C, apo B, CRP protein and fibrinogen. By contrast, phospholipid-PUFA were inversely associated with CRP, but not with any of the lipids. A higher SFA content (top v. bottom quarter) was associated with a 2-fold higher risk of CHD (OR and 95% CI: OR 2.12; 95% CI: 1.13, 3.99), and an equivalent difference in PUFA was associated with a halving in CHD risk (OR 0.49; 95% CI: 0.26, 0.94), but MUFA was unrelated to CHD risk. These associations were substantially attenuated, after additional adjustment for lipids and inflammatory markers. Higher levels of saturated fat and lower levels of polyunsaturated fats were each associated with a higher risk of CHD in elderly men, and these associations were partly explained by their effects on blood lipids and biomarkers of inflammation

    Mapping pneumonia research: a systematic analysis of UK investments and published outputs 1997–2013

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    BackgroundThe burden of pneumonia continues to be substantial, particularly among the poorest in global society. We describe here the trends for UK pneumonia R&amp;D investment and published outputs, and correlate with 2013 global mortality.MethodsData related to awards to UK institutions for pneumonia research from 1997 to 2013 were systematically sourced and categorised by disease area and type of science. Investment was compared to mortality figures in 2010 and 2013 for pneumonia, tuberculosis and influenza. Investment was also compared to publication data.ResultsOf all infectious disease research between 2011 and 2013 (£917.0 million), £28.8 million (3.1%) was for pneumonia. This was an absolute and proportionate increase from previous time periods. Translational pneumonia research (33.3%) received increased funding compared with 1997–2010 where funding was almost entirely preclinical (87.5%, here 30.9%), but high-burden areas such as paediatrics, elderly care and antimicrobial resistance received little investment. Annual investment remains volatile; publication temporal trends show a consistent increase. When comparing investment to global burden with a novel ‘investment by mortality observed’ metric, tuberculosis (£48.36) and influenza (£484.21) receive relatively more funding than pneumonia (£43.08), despite investment for pneumonia greatly increasing in 2013 compared to 2010 (£7.39). Limitations include a lack of private sector data and the need for careful interpretation of the comparisons with burden, plus categorisation is subjective.ConclusionsThere has been a welcome increase for pneumonia funding awarded to UK institutions in 2011–2013 compared with 1997–2010, along with increases for more translational research. Published outputs relating to pneumonia rose steadily from 1997 to 2013. Investment relative to mortality for pneumonia has increased, but it remains low compared to other respiratory infections and clear inequities remain. Analyses that measure investments in pneumonia can provide an insight into funding trends and research gaps.Research in contextPneumonia continues to be a high-burden illness around the globe. This paper shows that although research funding is increasing in the UK (between 1997 and 2013), it remains poorly funded compared to other important respiratory infectious diseases such as tuberculosis and influenza. Publications about pneumonia have been steadily increasing over time, indicating continuing academic and clinical interest in the topic. Though global mortality of pneumonia is declining, it should still be an area of high priority for funders, policymakers and researchers

    Dynamic Energy Management

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    We present a unified method, based on convex optimization, for managing the power produced and consumed by a network of devices over time. We start with the simple setting of optimizing power flows in a static network, and then proceed to the case of optimizing dynamic power flows, i.e., power flows that change with time over a horizon. We leverage this to develop a real-time control strategy, model predictive control, which at each time step solves a dynamic power flow optimization problem, using forecasts of future quantities such as demands, capacities, or prices, to choose the current power flow values. Finally, we consider a useful extension of model predictive control that explicitly accounts for uncertainty in the forecasts. We mirror our framework with an object-oriented software implementation, an open-source Python library for planning and controlling power flows at any scale. We demonstrate our method with various examples. Appendices give more detail about the package, and describe some basic but very effective methods for constructing forecasts from historical data.Comment: 63 pages, 15 figures, accompanying open source librar

    Healthcare-associated outbreak of meticillin-resistant Staphylococcus aureus bacteraemia: role of a cryptic variant of an epidemic clone

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    BACKGROUND New strains of meticillin-resistant Staphylococcus aureus (MRSA) may be associated with changes in rates of disease or clinical presentation. Conventional typing techniques may not detect new clonal variants that underlie changes in epidemiology or clinical phenotype. AIM To investigate the role of clonal variants of MRSA in an outbreak of MRSA bacteraemia at a hospital in England. METHODS Bacteraemia isolates of the major UK lineages (EMRSA-15 and -16) from before and after the outbreak were analysed by whole-genome sequencing in the context of epidemiological and clinical data. For comparison, EMRSA-15 and -16 isolates from another hospital in England were sequenced. A clonal variant of EMRSA-16 was identified at the outbreak hospital and a molecular signature test designed to distinguish variant isolates among further EMRSA-16 strains. FINDINGS By whole-genome sequencing, EMRSA-16 isolates during the outbreak showed strikingly low genetic diversity (P < 1 × 10(-6), Monte Carlo test), compared with EMRSA-15 and EMRSA-16 isolates from before the outbreak or the comparator hospital, demonstrating the emergence of a clonal variant. The variant was indistinguishable from the ancestral strain by conventional typing. This clonal variant accounted for 64/72 (89%) of EMRSA-16 bacteraemia isolates at the outbreak hospital from 2006. CONCLUSIONS Evolutionary changes in epidemic MRSA strains not detected by conventional typing may be associated with changes in disease epidemiology. Rapid and affordable technologies for whole-genome sequencing are becoming available with the potential to identify and track the emergence of variants of highly clonal organisms

    Desperate housewives: An analysis of the characterisations of female gamblers portrayed in gambling movies in Hong Kong

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    This article examines portrayals of female gamblers in recent Hong Kong movies. The authors report that the depiction of female gamblers is very different from that of male gamblers in the movies made in the same period. Whereas the male gamblers are pitching a lonely and desperate battle against the evil opponent, the female gamblers portrayed in the movies are housewives or small-time players who gamble only for their personal gain. A general negative overtone in portrayals of female gamblers was interpreted as a reflection of the traditional view that discourages women from gambling. The shift of gambling themes in the Hong Kong movies has been identified to reflect the most salient concerns among Hong Kong residents. Such changes are attributed to particular social and cultural changes in the community
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