2,660 research outputs found

    Fundamental nursing care: a systematic review of the evidence on the effect of nursing care interventions for nutrition, elimination, mobility and hygiene

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    This is the final version of the article. Available from Wiley via the DOI in this record.AIMS AND OBJECTIVES: To determine the effects of nursing interventions for people's nutrition, elimination, mobility and hygiene needs. BACKGROUND: Patient experience of health care is sensitive to nursing quality. A refocus on fundamental nursing care is undermined by lack of evidence of effectiveness for interventions in core areas such as elimination, nutrition, mobility and hygiene. DESIGN: SYSTEMATIC REVIEW: METHODS: We searched for and included experimental studies on interventions by professionally qualified and unregistered nurses that addressed participants' nutrition, elimination, mobility and hygiene needs. We extracted data on scope, quality and results of studies followed by descriptive narrative synthesis of included study outcomes using a novel form of harvest plots. RESULTS: We included 149 studies, 35 nutrition, 56 elimination, 16 mobility, 39 hygiene, and three addressing two or more areas simultaneously (67 randomised controlled trials (RCTs), 32 non-RCTs and 50 uncontrolled trials). Studies into interventions on participant self-management of nutrition (n=25), oral health (n=26), catheter care (n=23), and self-management of elimination (n=21) were the most prevalent. Most studies focussed their outcomes on observational or physiological measures, with very few collecting patient reported outcomes, such as quality of life, experience or self-reported symptoms. All but 13 studies were of low quality and at significant risk of bias. The majority of studies did not define primary outcomes, included multiple measures of identical concepts, used inappropriate analyses, and did not conform to standard reporting quality criteria. CONCLUSIONS: The current evidence for fundamental nursing care interventions is sparse, of poor quality and unfit to provide evidence-based guidance to practising nurses. This article is protected by copyright. All rights reserved.This study was funded by a Programme Development Grant from the UK National Institute of Health Research (NIHR). RP-DG-1214-10001. David Richards and Victoria Goodwin receive funding support from the UK National Institute for Health Research South West Peninsula Collaboration for Leadership in Applied Health Research and Care

    Corotating light cylinders and Alfv\'en waves

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    Exact relativistic force free fields with cylindrical symmetry are explored. Such fields are generated in the interstellar gas via their connection to pulsar magnetospheres both inside and outside their light cylinders. The possibility of much enhanced interstellar fields wound on cylinders of Solar system dimensions is discussed but these are most likely unstable.Comment: 6 pages, 6 figures, accepted by MNRA

    Structural Parameters of Seven SMC Intermediate-Age and Old Star Clusters

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    We present structural parameters for the seven intermediate-age and old star clusters NGC121, Lindsay 1, Kron 3, NGC339, NGC416, Lindsay 38, and NGC419 in the Small Magellanic Cloud. We fit King profiles and Elson, Fall, and Freeman profiles to both surface-brightness and star count data taken with the Advanced Camera for Surveys aboard the Hubble Space Telescope. Clusters older than 1 Gyr show a spread in cluster core radii that increases with age, while the youngest clusters have relatively compact cores. No evidence for post core collapse clusters was found. We find no correlation between core radius and distance from the SMC center, although consistent with other studies of dwarf galaxies, some relatively old and massive clusters have low densities. The oldest SMC star cluster, the only globular NGC121, is the most elliptical object of the studied clusters. No correlation is seen between ellipticity and distance from the SMC center. The structures of these massive intermediate-age (1-8 Gyr) SMC star clusters thus appear to primarily result from internal evolutionary processes.Comment: 16 pages, 13 figure

    Testing the universality of star formation - I. Multiplicity in nearby star-forming regions

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    We have collated multiplicity data for five clusters (Taurus, Chamaeleon I, Ophiuchus, IC348, and the Orion Nebula Cluster). We have applied the same mass ratio (flux ratios of delta K <= 2.5) and primary mass cuts (~0.1-3.0 Msun) to each cluster and therefore have directly comparable binary statistics for all five clusters in the separation range 62-620 au, and for Taurus, Chamaeleon I, and Ophiuchus in the range 18-830 au. We find that the trend of decreasing binary fraction with cluster density is solely due to the high binary fraction of Taurus, the other clusters show no obvious trend over a factor of nearly 20 in density. With N-body simulations we attempt to find a set of initial conditions that are able to reproduce the density, morphology and binary fractions of all five clusters. Only an initially clumpy (fractal) distribution with an initial total binary fraction of 73 per cent (17 per cent in the range 62-620 au) is able to reproduce all of the observations (albeit not very satisfactorily). Therefore, if star formation is universal the initial conditions must be clumpy and with a high (but not 100 per cent) binary fraction. This could suggest that most stars, including M-dwarfs, form in binaries.Comment: Accepted for publication in MNRAS, 19 pages, 22 figure

    Spatial differences between stars and brown dwarfs: a dynamical origin?

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    We use NN-body simulations to compare the evolution of spatial distributions of stars and brown dwarfs in young star-forming regions. We use three different diagnostics; the ratio of stars to brown dwarfs as a function of distance from the region's centre, RSSR\mathcal{R}_{\rm SSR}, the local surface density of stars compared to brown dwarfs, ΣLDR\Sigma_{\rm LDR}, and we compare the global spatial distributions using the ΛMSR\Lambda_{\rm MSR} method. From a suite of twenty initially statistically identical simulations, 6/20 attain RSSR<<1\mathcal{R}_{\rm SSR} << 1 andand ΣLDR<<1\Sigma_{\rm LDR} << 1 andand ΛMSR<<1\Lambda_{\rm MSR} << 1, indicating that dynamical interactions could be responsible for observed differences in the spatial distributions of stars and brown dwarfs in star-forming regions. However, many simulations also display apparently contradictory results - for example, in some cases the brown dwarfs have much lower local densities than stars (ΣLDR<<1\Sigma_{\rm LDR} << 1), but their global spatial distributions are indistinguishable (ΛMSR=1\Lambda_{\rm MSR} = 1) and the relative proportion of stars and brown dwarfs remains constant across the region (RSSR=1\mathcal{R}_{\rm SSR} = 1). Our results suggest that extreme caution should be exercised when interpreting any observed difference in the spatial distribution of stars and brown dwarfs, and that a much larger observational sample of regions/clusters (with complete mass functions) is necessary to investigate whether or not brown dwarfs form through similar mechanisms to stars.Comment: 7 pages, 5 figures, accepted for publication in MNRA

    Newly Identified Star Clusters in M33. III. Structural Parameters

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    We present the morphological properties of 161 star clusters in M33 using the Advanced Camera For Surveys Wide Field Channel onboard the Hubble Space Telescope using observations with the F606W and F814W filters. We obtain, for the first time, ellipticities, position angles, and surface brightness profiles for a significant number of clusters. On average, M33 clusters are more flattened than those of the Milky Way and M31, and more similar to clusters in the Small Magellanic Cloud. The ellipticities do not show any correlation with age or mass, suggesting that rotation is not the main cause of elongation in the M33 clusters. The position angles of the clusters show a bimodality with a strong peak perpendicular to the position angle of the galaxy major axis. These results support the notion that tidal forces are the reason for the cluster flattening. We fit King and EFF models to the surface brightness profiles and derive structural parameters including core radii, concentration, half-light radii and central surface brightness for both filters. The surface brightness profiles of a significant number of clusters show irregularities such as bumps and dips. Young clusters (Log age < 8) are notably better fitted by models with no radial truncation (EFF models), while older clusters show no significant differences between King or EFF fits. M33 star clusters seem to have smaller sizes, smaller concentrations, and smaller central surface brightness as compared to clusters in the MW, M31, LMC and SMC. Analysis of the structural parameters presents a age-radius relation also detected in other star cluster systems. The overall analysis shows differences in the structural evolution between the M33 cluster system and cluster systems in nearby galaxies. These differences could have been caused by the strong differences in these various environments.Comment: 30 pages, 12 figures, accepted for publication in MNRA

    Structures in surface-brightness profiles of LMC and SMC star clusters: evidence of mergers?

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    The LMC and SMC are rich in binary star clusters, and some mergers are expected. It is important to characterize single clusters, binary clusters and candidates to mergers. We selected a sample of star clusters in each Cloud with this aim. Surface photometry of 25 SMC and 22 LMC star clusters was carried with the ESO Danish 1.54 m telescope. 23 clusters were observed for the first time for these purposes. We fitted Elson, Fall and Freeman (1987, EFF) profiles to the data, deriving structural parameters, luminosities and masses. We also use isophotal maps to constrain candidates to cluster interactions.} {The structural parameters, luminosities and masses presented good agreement with those in the literature. Three binary clusters in the sample have a double profile. Four clusters (NGC 376, K 50, K 54 and NGC 1810) do not have companions and present as well important deviations from EFF profiles. The present sample contains blue and red Magellanic clusters. Extended EFF profiles were detected in some blue clusters. We find evidence that important deviations from the body of EFF profiles might be used as a tool to detect cluster mergers.Comment: 16 pages and 8 figures. Accepted by A&

    Evolutionary relationships between Rhynchosporium lolii sp. nov. and other Rhynchosporium species on grass.

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    Copyright: 2013 King et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedThe fungal genus Rhynchosporium (causative agent of leaf blotch) contains several host-specialised species, including R. commune (colonising barley and brome-grass), R. agropyri (couch-grass), R. secalis (rye and triticale) and the more distantly related R. orthosporum (cocksfoot). This study used molecular fingerprinting, multilocus DNA sequence data, conidial morphology, host range tests and scanning electron microscopy to investigate the relationship between Rhynchosporium species on ryegrasses, both economically important forage grasses and common wild grasses in many cereal growing areas, and other plant species. Two different types of Rhynchosporium were found on ryegrasses in the UK. Firstly, there were isolates of R. commune that were pathogenic to both barley and Italian ryegrass. Secondly, there were isolates of a new species, here named R. lolii, that were pathogenic only to ryegrass species. R. lolii was most closely related to R. orthosporum, but exhibited clear molecular, morphological and host range differences. The species was estimated to have diverged from R. orthosporum ca. 5735 years before the present. The colonisation strategy of all of the different Rhynchosporium species involved extensive hyphal growth in the sub-cuticular regions of the leaves. Finally, new species-specific PCR diagnostic tests were developed that could distinguish between these five closely related Rhynchosporium species.Peer reviewedFinal Published versio

    The influence of stellar-dynamical ejections and collisions on the relation between the maximum-star and star-cluster-mass

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    We perform the largest currently available set of direct N-body calculations of young star cluster models to study the dynamical influence, especially through the ejections of the most massive star in the cluster, on the current relation between the maximum-stellar-mass and the star-cluster-mass. We vary several initial parameters such as the initial half-mass radius of the cluster, the initial binary fraction, and the degree of initial mass segregation. Two different pairing methods are used to construct massive binaries for more realistic initial conditions of massive binaries. We find that lower mass clusters (<= 10^2.5 Msun) do not shoot out their heaviest star. In the case of massive clusters (>= 1000 Msun), no most-massive star escapes the cluster within 3 Myr regardless of the initial conditions if clusters have initial half-mass radii, r_0.5, >= 0.8 pc. However, a few of the initially smaller sized clusters (r_0.5 = 0.3 pc), which have a higher density, eject their most massive star within 3 Myr. If clusters form with a compact size and their massive stars are born in a binary system with a mass-ratio biased towards unity, the probability that the mass of the most massive star in the cluster changes due to the ejection of the initially most massive star can be as large as 20 per cent. Stellar collisions increase the maximum-stellar-mass in a large number of clusters when clusters are relatively dense (M_ecl >= 10^3 Msun and r_0.5 = 0.3 pc) and binary-rich. Overall, we conclude that dynamical effects hardly influence the observational maximum-stellar-mass -- cluster mass relation.Comment: 16 pages, 8 figures, 5 tables, accepted for publication in MNRA
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