472 research outputs found

    Medlinella amphoroidea gen. et sp. nov. (Bacillariophyta) from the neck skin of Loggerhead sea turtles (Caretta caretta)

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    Medlinella amphoroidea gen. et sp. nov. is described from the dorsal neck skin of loggerhead sea turtles (Caretta caretta). The presence of girdle septa, multiple copulae, and the marine epizoic habitat of Medlinella amphoroidea are characteristic features shared with many species in the similar Tripterion, Chelonicola, and Poulinea genera. The semi-lanceolate valve shape, the asymmetric valve face with distinct dorsal and ventral striae, and the volate pore occlusions distinguish Medlinella from these genera. Medlinella amphoroidea accounted for up to 50% of all diatom valves on the skin of examined loggerhead turtles. Examination of the type slides of Tripterion kalamensis and T. philoderma for comparative purposes revealed morphological features that were either insufficiently or incorrectly described in the original publications. Our observations confirm that T. philoderma lacks septa and therefore does not conform to the genus description of Tripterion. The description of cingulum structure in Tripterion kalamensis is amended to identify multiple porose copulae that are open at one end. While the description of Medlinella creates another monotypic genus within a group of similar marine epizoic genera, we feel the novel character state (volate occlusions) present in this taxon is significant. Clearly, however, further phylogenetic analysis of morphological, or the development of molecular characters in the group of similar genera is required

    The business of cultural heritage tourism: critical success factors

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    This paper explores critical success factors (CSFs) required for cultural heritage tourism (CHT) operation and how these relate to commercial focus. The literature indicates tension between conservation of authenticity and commercial focus as it is seen to undermine authenticity, potentially degrading its quality and ultimate success as a tourism product. A list of nine key CHT business success factors was devised based on the published literature. Managers and operators of a range of Australian CHT operations were interviewed regarding achievement of CSFs. The operations were broadly categorised according to the level of commercial focus. The level of commercial focus was cross tabulated with the number of CHT business CSFs achieved. While all places in this study had addressed authenticity, CHT places presenting highly commercialised products tended to meet the criteria for achieving a greater number of CSFs than their less commercialised counter-parts. This has implications for sustainable CHT operation practices

    The Central X-Ray Point Source in Cassiopeia A

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    The spectacular first light observation by the Chandra X-Ray Observatory revealed an X-ray point source near the center of the 300 yr old Cas A supernova remnant. We present an analysis of the public X-ray spectral and timing data. No coherent pulsations were detected in the Chandra/HRC data. The 3-sigma upper limit on the pulsed fraction is 20 ms. The Chandra/ACIS spectrum of the point source may be fit with an ideal blackbody (kT=0.5 keV), or with BB models modified by the presence of a NS atmosphere (kT=0.25-0.35 keV), but the temperature is higher and the inferred emitting area lower than expected for a 300 yr old NS according to standard cooling models. The spectrum may also be fit with a power law model (photon index 2.8-3.6). Both the spectral properties and the timing limits of the point source are inconsistent with a young Crab-like pulsar, but are quite similar to the properties of the anomalous X-ray pulsars. The spectral parameters are also very similar to those of the other radio-quiet X-ray point sources in the supernova remnants Pup A, RCW 103, and PKS 1209-52. Current limits on an optical counterpart for the Cas A point source rule out models that invoke fallback accretion onto a compact object if fallback disk properties are similar to those in quiescent low-mass X-ray binaries. However, the optical limits are marginally consistent with plausible alternative assumptions for a fallback disk. In this case, accreting NS models can explain the X-ray data, but an accreting BH model is not promising.Comment: 17 pages including 2 figs. To appear in ApJ, Vol. 546 (Jan 10, 2001). Minor revisions per referee. Pulsation limits revised in light of HRC wiring problem. Typos correcte

    The expansion asymmetry and age of the Cassiopeia A supernova remnant

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    HST images of the young supernova remnant Cas A are used to explore the expansion and spatial distribution of its highest velocity debris. ACS WFC images taken in 2004 March and December with Sloan F625W, F775W, and F850LP filters were used to identify 1825 high-velocity, outlying ejecta knots through measured proper motions of 0."35 - 0."90 yr(-1), corresponding to V-trans = 5500-14,500 km s(-1) assuming d = 3.4 kpc. The distribution of derived transverse expansion velocities for these ejecta knots shows a striking bipolar asymmetry with the highest velocity knots (V-trans >= 10,500 km s(-1)) confined to nearly opposing northeast and southwest "jets'' at P.A. = 45 degrees-70 degrees and 230 degrees-270 degrees, respectively. The jets have about the same maximum expansion velocity of similar or equal to 14,000 km s(-1) and appear kinematically and chemically distinct in that they are the remnant's only S-rich ejecta with expansion velocities above the 10,000-11,000 km s(-1) exhibited by outer nitrogen-rich ejecta, which otherwise represent the remnant's highest velocity debris. In addition, we find significant gaps in the spatial distribution of outlying ejecta in directions that are approximately perpendicular to the jets (P.A. = 145 degrees-200 degrees and 335 degrees-350 degrees). The remnant's central X-ray point source lies some 700 to the southeast of the estimated expansion center ( P.A. = 169 degrees +/- 8.degrees 4) indicating a projected motion toward the middle of the broad southern ejecta knot gap. Extrapolations of measured 9 month proper motions for all 1825 outer ejecta knots and a selected subsample of 72 bright and compact knots suggest explosion dates (assuming no knot deceleration) of 1662 +/- 27 and 1672 +/- 18, respectively. We find some evidence for nonuniform deceleration in different directions around the remnant and find 126 knots located along the northwestern limb among the least decelerated ejecta, suggesting a convergence date of 1681 +/- 19. A remnant age of around 325 yr would imply a +/- 350 km s(-1) transverse velocity for the central X-ray point source

    Electronically delivered, multicomponent intervention to reduce unnecessary antibiotic prescribing for respiratory infections in primary care: a cluster randomised trial using electronic health records—REDUCE Trial study original protocol

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    Introduction Respiratory tract infections (RTIs) account for about 60% of antibiotics prescribed in primary care. This study aims to test the effectiveness, in a cluster randomised controlled trial, of electronically delivered, multicomponent interventions to reduce unnecessary antibiotic prescribing when patients consult for RTIs in primary care. The research will specifically evaluate the effectiveness of feeding back electronic health records (EHRs) data to general practices. Methods and analysis 2-arm cluster randomised trial using the EHRs of the Clinical Practice Research Datalink (CPRD). General practices in England, Scotland, Wales and Northern Ireland are being recruited and the general population of all ages represents the target population. Control trial arm practices will continue with usual care. Practices in the intervention arm will receive complex multicomponent interventions, delivered remotely to information systems, including (1) feedback of each practice's antibiotic prescribing through monthly antibiotic prescribing reports estimated from CPRD data; (2) delivery of educational and decision support tools; (3) a webinar to explain and promote effective usage of the intervention. The intervention will continue for 12?months. Outcomes will be evaluated from CPRD EHRs. The primary outcome will be the number of antibiotic prescriptions for RTIs per 1000 patient years. Secondary outcomes will be: the RTI consultation rate; the proportion of consultations for RTI with an antibiotic prescribed; subgroups of age; different categories of RTI and quartiles of intervention usage. There will be more than 80% power to detect an absolute reduction in antibiotic prescription for RTI of 12 per 1000 registered patient years. Total healthcare usage will be estimated from CPRD data and compared between trial arms. Ethics and dissemination Trial protocol was approved by the National Research Ethics Service Committee (14/LO/1730). The pragmatic design of the trial will enable subsequent translation of effective interventions at scale in order to achieve population impact. <br/

    Effectiveness and cost-effectiveness of an educational intervention for practice teams to deliver problem focused therapy for insomnia: rationale and design of a pilot cluster randomised trial

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    Background: Sleep problems are common, affecting over a third of adults in the United Kingdom and leading to reduced productivity and impaired health-related quality of life. Many of those whose lives are affected seek medical help from primary care. Drug treatment is ineffective long term. Psychological methods for managing sleep problems, including cognitive behavioural therapy for insomnia (CBTi) have been shown to be effective and cost effective but have not been widely implemented or evaluated in a general practice setting where they are most likely to be needed and most appropriately delivered. This paper outlines the protocol for a pilot study designed to evaluate the effectiveness and cost-effectiveness of an educational intervention for general practitioners, primary care nurses and other members of the primary care team to deliver problem focused therapy to adult patients presenting with sleep problems due to lifestyle causes, pain or mild to moderate depression or anxiety. Methods and design: This will be a pilot cluster randomised controlled trial of a complex intervention. General practices will be randomised to an educational intervention for problem focused therapy which includes a consultation approach comprising careful assessment (using assessment of secondary causes, sleep diaries and severity) and use of modified CBTi for insomnia in the consultation compared with usual care (general advice on sleep hygiene and pharmacotherapy with hypnotic drugs). Clinicians randomised to the intervention will receive an educational intervention (2 × 2 hours) to implement a complex intervention of problem focused therapy. Clinicians randomised to the control group will receive reinforcement of usual care with sleep hygiene advice. Outcomes will be assessed via self-completion questionnaires and telephone interviews of patients and staff as well as clinical records for interventions and prescribing. Discussion: Previous studies in adults have shown that psychological treatments for insomnia administered by specialist nurses to groups of patients can be effective within a primary care setting. This will be a pilot study to determine whether an educational intervention aimed at primary care teams to deliver problem focused therapy for insomnia can improve sleep management and outcomes for individual adult patients presenting to general practice. The study will also test procedures and collect information in preparation for a larger definitive cluster-randomised trial. The study is funded by The Health Foundation

    Selection of Medical Diagnostic Codes for Analysis of Electronic Patient Records. Application to Stroke in a Primary Care Database

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    BACKGROUND: Electronic patient records from primary care databases are increasingly used in public health and health services research but methods used to identify cases with disease are not well described. This study aimed to evaluate the relevance of different codes for the identification of acute stroke in a primary care database, and to evaluate trends in the use of different codes over time.METHODS: Data were obtained from the General Practice Research Database from 1997 to 2006. All subjects had a minimum of 24 months of up-to-standard record before the first recorded stroke diagnosis. Initially, we identified stroke cases using a supplemented version of the set of codes for prevalent stroke used by the Office for National Statistics in Key health statistics from general practice 1998 (ONS codes). The ONS codes were then independently reviewed by four raters and a restricted set of 121 codes for 'acute stroke' was identified but the kappa statistic was low at 0.23.RESULTS: Initial extraction of data using the ONS codes gave 48,239 cases of stroke from 1997 to 2006. Application of the restricted set of codes reduced this to 39,424 cases. There were 2,288 cases whose index medical codes were for 'stroke annual review' and 3,112 for 'stroke monitoring'. The frequency of stroke review and monitoring codes as index codes increased from 9 per year in 1997 to 1,612 in 2004, 1,530 in 2005 and 1,424 in 2006. The one year mortality of cases with the restricted set of codes was 29.1% but for 'stroke annual review,' 4.6% and for 'stroke monitoring codes', 5.7%.CONCLUSION: In the analysis of electronic patient records, different medical codes for a single condition may have varying clinical and prognostic significance; utilisation of different medical codes may change over time; researchers with differing clinical or epidemiological experience may have differing interpretations of the relevance of particular codes. There is a need for greater transparency in the selection of sets of codes for different conditions, for the reporting of sensitivity analyses using different sets of codes, as well as sharing of code sets among researchers
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