2,083 research outputs found

    Statistics of the General Circulation from Cumulant Expansions

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    Large-scale atmospheric flows may not be so nonlinear as to preclude their statistical description by systematic expansions in cumulants. I extend previous work by examining a two-layer baroclinic model of the general circulation. The fixed point of the cumulant expansion describes the statistically steady state of the out-of-equilibrium model. Equal-time statistics so obtained agree well with those accumulated by direct numerical simulation.Comment: 1 page paper with 4 figures that accompanies one of the winning entries in the APS gallery of nonlinear images competitio

    Self reported aggravating activities do not demonstrate a consistent directional pattern in chronic non specific low back pain patients: An observational study

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    Question: Do the self-reported aggravating activities of chronic non-specific low back pain patients demonstrate a consistent directional pattern? Design: Cross-sectional observational study. Participants: 240 chronic non specific low back pain patients. Outcome measure: We invited experienced clinicians to classify each of the three self-nominated aggravating activities from the Patient Specific Functional Scale by the direction of lumbar spine movement. Patients were described as demonstrating a directional pattern if all nominated activities moved the spine into the same direction. Analyses were undertaken to determine if the proportion of patients demonstrating a directional pattern was greater than would be expected by chance. Results: In some patients, all tasks did move the spine into the same direction, but this proportion did not differ from chance (p = 0.328). There were no clinical or demographic differences between those who displayed a directional pattern and those who did not (all p > 0.05). Conclusion: Using patient self-reported aggravating activities we were unable to demonstrate the existence of a consistent pattern of adverse movement in patients with chronic non-specific low back pain

    BCS pairing in Fermi systems with several flavors

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    Motivated by the prospect of Bardeen-Cooper-Schrieffer (BCS) pairing in cold fermionic gases we analyze the superfluid phase of 3 fermionic flavors in the attractive Hubbard model. We show that there are several low--lying collective pairing modes and investigate their damping due to the partially gapless nature of the single-particle spectrum. Furthermore we analyze how these modes show up in the density response of the system. Apart from the Anderson-Bogoliubov phase mode of the pairing between two flavors, the dynamical structure factor contains signatures of the gapless third flavor. This picture is found to be robust against perturbations that break the global SU(3)-symmetry of the Hamiltonian.Comment: 13 pages, 6 figure

    Threshold Star Formation Effects in the Peculiar Galaxy Arp~10 (=~VV 362)

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    We present images of the peculiar galaxy Arp~10 which reveal two rings of concurrent star formation. Apart from a bright ring visible on early photographs of the system, an even brighter inner ring of \ion{H}{2} regions is found within the nuclear bulge of the galaxy. A very faint ring-arc of \ion{H}{2} regions is also seen associated with a third outer ring or shell. An investigation of the Hα\alpha fluxes in the rings reveals an increase in the emission where the ring surface density in the R-band light exceeds 21.3±\pm0.2 mag arcsec−2^{-2}. If the R-band light is dominated by old stars in the underlying density wave, then the results suggest evidence for a Star Formation law which exhibits a threshold dependence on the strength of the density wave in the rings. Even if the R-band continuum in the ring is heavily contaminated with red light from the underlying young stars then a smaller, but still significant non-linear enhancement in the star formation rates (SFR) in one segment of the second ring is required to explain the results. In either case, strong trends in the SFR with azimuth around Ring~2 are in good agreement with off-center collisional ring galaxy models.Comment: 14 Pages, LaTeX AASTeX macros v3.0, 11 figures (available upon request), Ap.J. (accepted, to appear 09/1/93), ISU-VC-93-

    Results of a pilot cluster randomised trial of the use of a Medication Review Tool for people taking antipsychotic medication

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    BACKGROUND: Government policy encourages increasing involvement of patients in their long-term care. This paper describes the development and pilot evaluation of a 'Medication Review Tool' designed to assist people to participate more effectively in discussions about antipsychotic drug treatment. METHODS: The Medication Review Tool developed consisted of a form to help patients identify pros and cons of their current antipsychotic treatment and any desired changes. It was associated with a website containing information and links about antipsychotics. For the trial, participants diagnosed with psychotic disorders were recruited from community mental health services. Cluster randomisation was used to allocate health professionals (care co-ordinators) and their associated patients to use of the Medication Review Tool or usual care. All participants had a medical consultation scheduled, and those in the intervention group completed the Medication Review Tool, with the help of their health professional prior to this, and took the completed Form into the consultation. Two follow-up interviews were conducted up to three months after the consultation. The principal outcome was the Decision Self Efficacy Scale (DSES). Qualitative feedback was collected from patients in the intervention group. RESULTS: One hundred and thirty patients were screened, sixty patients were randomised, 51 completed the first follow-up assessment and 49 completed the second. Many patients were not randomised due to the timing of their consultation, and involvement of health professionals was inconsistent. There was no difference between the groups on the DSES (-4.16 95 % CI -9.81, 1.49), symptoms, side effects, antipsychotic doses or patient satisfaction. Scores on the Medication Adherence Questionnaire indicated an increase in participants' reported inclination to adherence in the intervention group (coefficient adjusted for baseline values -0.44; 95 % CI -0.76, -0.11), and there was a small increase in positive attitudes to antipsychotic medication (Drug Attitude Inventory, adjusted coefficient 1.65; 95 % CI -0.09, 3.40). Qualitative feedback indicated patients valued the Tool for identifying both positive and negative aspects of drug treatment. CONCLUSIONS: The trial demonstrated the design was feasible, although challenges included service re-configurations and maintaining health professional involvement. Results may indicate a more intensive and sustained intervention is required to facilitate participation in decision-making for this group of patients. TRIAL REGISTRATION: Current controlled trials ISRCTN12055530 , Retrospectively registered 9/12/2013

    Assessment of left atrial volume before and after pulmonary thromboendarterectomy in chronic thromboembolic pulmonary hypertension.

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    BackgroundImpaired left ventricular diastolic filling is common in chronic thromboembolic pulmonary hypertension (CTEPH), and recent studies support left ventricular underfilling as a cause. To investigate this further, we assessed left atrial volume index (LAVI) in patients with CTEPH before and after pulmonary thromboendarterectomy (PTE).MethodsForty-eight consecutive CTEPH patients had pre- & post-PTE echocardiograms and right heart catheterizations. Parameters included mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index, LAVI, & mitral E/A ratio. Echocardiograms were performed 6 ± 3 days pre-PTE and 10 ± 4 days post-PTE. Regression analyses compared pre- and post-PTE LAVI with other parameters.ResultsPre-op LAVI (mean 19.0 ± 7 mL/m2) correlated significantly with pre-op PVR (R = -0.45, p = 0.001), mPAP (R = -0.28, p = 0.05) and cardiac index (R = 0.38, p = 0.006). Post-PTE, LAVI increased by 18% to 22.4 ± 7 mL/m2 (p = 0.003). This change correlated with change in PVR (765 to 311 dyne-s/cm5, p = 0.01), cardiac index (2.6 to 3.2 L/min/m2, p = 0.02), and E/A (.95 to 1.44, p = 0.002).ConclusionIn CTEPH, smaller LAVI is associated with lower cardiac output, higher mPAP, and higher PVR. LAVI increases by ~20% after PTE, and this change correlates with changes in PVR and mitral E/A. The rapid increase in LAVI supports the concept that left ventricular diastolic impairment and low E/A pre-PTE are due to left heart underfilling rather than inherent left ventricular diastolic dysfunction

    Incidence, age at diagnosis and survival with dementia across ethnic groups in England: A longitudinal study using electronic health records.

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    INTRODUCTION: We investigated the incidence of diagnosed dementia and whether age at diagnosis and survival afterward differs among the United Kingdom's three largest ethnic groups. METHODS: We used primary care electronic health records, linked Hospital Episode Statistics and mortality data for adults aged ≄65 years. We compared recorded dementia incidence 1997-2018, age at diagnosis, survival time and age at death after diagnosis in White, South Asian, and Black people. RESULTS: Dementia incidence was higher in Black people (incidence rate ratios [IRR] 1.22, 95% CI 1.15-1.30). South Asian and Black people with dementia had a younger age of death than White participants (mean difference for South Asian participants -2.97 years, (95% CI -3.41 to -2.53); and Black participants -2.66 years, (95% CI -3.08 to -2.24). DISCUSSION: South Asian and Black peoples' younger age of diagnosis and death means targeted prevention and care strategies for these groups should be prioritized and tailored to facilitate take-up

    ANTLER statistical analysis plan, Version 3, 16 January 2020

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    This analysis plan sets out the methods of analysing the predetermined primary, secondary and health economic outcomes for ANTLER, which will be reported in the National Institute for Health Research, Health Technology Assessment report at the end of the trial and also in the main peer review paper(s) to result from this randomised controlled trial. The analysis and reporting of this trial will conform to the CONSORT and CHEERS statements and the appropriate standard operating procedures written by Priment Clinical Trials Unit. Further information on this trial can be found in the protocol version 7.0 (26/11/2018). The protocol is stored on: S:\Pop_Health\PCPH_Priment\Projects\Current\CTIMPS\ANTLER\6. Protocol\ANTLER_protocol_v7_20181126.pdf

    Post-Foucauldian governmentality: what does it offer critical social policy analysis?

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    This article considers the theoretical perspective of post-Foucauldian governmentality, especially the insights and challenges it poses for applied researchers within the critical social policy tradition. The article firstly examines the analytical strengths of this approach to understanding power and rule in contemporary society, before moving on to consider its limitations for social policy. It concludes by arguing that these insights can be retained, and some of the weaknesses overcome, by adopting a ‘realist governmentality’ approach (Stenson 2005, 2008). This advocates combining traditional discursive analysis with more ethnographic methods in order to render visible the concrete activity of governing, and unravel the messiness, complexity and unintended consequences involved in the struggles around subjectivity
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