8,952 research outputs found

    A point mass in an isotropic universe: III. The region R≤2mR\leq 2m

    Full text link
    McVittie's solution of Einstein's field equations, representing a point mass embedded into an isotropic universe, possesses a scalar curvature singularity at proper radius R=2mR=2m. The singularity is space-like and precedes, in the expanding case, all other events in the space-time. It is shown here that this singularity is gravitationally weak, and the possible structure of the region R≤2mR\leq 2m is investigated. A characterization of this solution which does not involve asymptotics is given.Comment: Revtex, 11pp. To appear in Class.Quant.Grav. Paper II appeared as Class. Quant. Grav. 16 (1999) 122

    Health-related quality of life in the WA HIV Cohort: 2008

    Get PDF
    Quality of life (QOL) is an important outcome of HIV treatment and a priority in the management of HIV. A new Patient-Reported Outcomes (PRO) questionnaire to measure the QOL in people living with HIV/AIDS (PLWHA) from different cultures and language groups has been developed. The instrument, PROQOL-HIV, has undergone psychometric validation in 791 individuals from 8 countries including 99 people from the WA HIV Cohort Study

    Tropical cyclone rainbands can trigger meteotsunamis

    Get PDF
    © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Shi, L., Olabarrieta, M., Nolan, D. S., & Warner, J. C. Tropical cyclone rainbands can trigger meteotsunamis. Nature Communications, 11(1), (2020): 678, doi:10.1038/s41467-020-14423-9.Tropical cyclones are one of the most destructive natural hazards and much of the damage and casualties they cause are flood-related. Accurate characterization and prediction of total water levels during extreme storms is necessary to minimize coastal impacts. While meteotsunamis are known to influence water levels and to produce severe consequences, their impacts during tropical cyclones are underappreciated. This study demonstrates that meteotsunami waves commonly occur during tropical cyclones, and that they can contribute significantly to total water levels. We use an idealized coupled ocean–atmosphere–wave numerical model to analyze tropical cyclone-induced meteotsunami generation and propagation mechanisms. We show that the most extreme meteotsunami events are triggered by inherent features of the structure of tropical cyclones: inner and outer spiral rainbands. While outer distant spiral rainbands produce single-peak meteotsunami waves, inner spiral rainbands trigger longer lasting wave trains on the front side of the tropical cyclones.We thank all the developers of COAWST, ROMS, WRF, and SWAN models. D.N. was supported by NSF grant AGS-1654831. We would like to thank Dr. K. Bagamian for her editorial and writing suggestions. We would like to thank Dr. A. Aretxabaleta for the internal US Geological Survey internal revision and suggestions

    A note on behaviour at an isotropic singularity

    Get PDF
    The behaviour of Jacobi fields along a time-like geodesic running into an isotropic singularity is studied. It is shown that the Jacobi fields are crushed to zero length at a rate which is the same in every direction orthogonal to the geodesic. We show by means of a counter-example that this crushing effect depends crucially on a technicality of the definition of isotropic singularities, and not just on the uniform degeneracy of the metric at the singularity.Comment: 13 pp. plain latex. To appear in Classical and Quantum Gravit

    Prospective genetic screening decreases the incidence of Abacavir hypersensitivity reactions in the Western Australian HIV cohort study

    Get PDF
    Abacavir therapy is associated with significant drug hypersensitivity in ∼8% of recipients, with retrospective studies indicating a strong genetic association with the HLA-B*5701 allelle. In this prospective study, involving 260 abacavir-naive individuals (7.7% of whom were positive for HLA-B*5701), we confirm the usefulness of genetic risk stratification, with no cases of abacavir hypersensitivity among 148 HLA-B*5701–negative recipients

    CCD photometry of 2060 Chiron, 1991 January

    Get PDF
    Observations of 2060 Chiron was performed on 7 to 8 Jan. 1991 with the Mt. Palomar 1.52 m telescope in the Gunn-R passband. On-chip field stars were used to perform differential reductions. The repeatability of the 5.9 hour light curve was excellent, both within a night and from night to night. No evidence for short-term secular variations similar to those seen last year by both Luu and Jewitt (1990) and Buratti and Dunbar (1991) is seen in the new light curve. Chiron's rotational light curve appears strikingly similar to that obtained a year earlier by Luu and Jewitt (1990), both in amplitude and shape. Both light curves show strongly correlated changes over a timescale of perhaps 15 minutes. These same features were marginally visible in the 1986 light curve. Such behavior is believed to be evidence that Chiron may be more aspherical than the 4 percent intensity variation might otherwise indicate, and favors a viewing geometry where the subearth latitude is rather low. Chiron was much fainter in 1985, when a partial light curve was obtained by Marcialis. Due to the lower sampling rate of these early data, no conclusions can be made regarding the high-frequency light curve structure back then. All three of these light curves differ significantly from that obtained by Buratti and Dunbar (1991), one week before the observations of Luu and Jewitt. The Chiron field was calibrated using Landolt standards on Ut 15 Mar. 1991. A mean R-magnitude of 15.6 + or - 0.1 was found. Variability of 2060 Chiron was demonstrated over timescales of minutes, hours, and years. An intense campaign was urged to monitor the photometric behavior of Chiron throughout the 1990s

    Person-centred oral hydration care for older people with dementia admitted to acute hospital wards: Empirical research qualitative.

    Get PDF
    To conduct an in-depth exploration of oral hydration care provided to people living with dementia in acute hospital wards, using a person-centred care framework. Oral hydration care is an important, yet rarely explored aspect of fundamental care for people with dementia admitted to acute hospitals. Using person-centred care as a conceptual framework we investigated how oral hydration care is delivered for people living with dementia in acute hospital wards. A qualitative, multiple-case study. The cases were three acute wards in one hospital. Direct observation of care for 13 people with dementia (132 h), semistructured interviews with ward staff (n = 28), ward leaders (n = 4), organisational leaders (n = 5), people with dementia (n = 6), their relatives (n = 5), documentary analysis of clinical inpatient records (n = 26) and relevant hospital policies. Data were analysed using framework analysis. Four themes were identified: (1) The acute hospital: oral hydration is obscured and not prioritised (2) Overshadowing of oral hydration at ward level (3) Siloed nature of hydration roles (4) Strategies for, and barriers to, delivering person-centred oral hydration care. This study combines the concept of person-centred care and oral hydration care for people living with dementia admitted to acute hospital wards, demonstrating that person-centred hydration care was complex and not prioritised. Nurses should consider means of improving prioritisation and cohesive delivery of person-centred hydration care in acute hospital wards. [Abstract copyright: © 2023 The Authors. Journal of Clinical Nursing published by John Wiley & Sons Ltd.

    Guest Editorial - Special Issue June 2016: ESLTIS 2015 - Conference Special Issue

    Get PDF
    In this short editorial, we’ll discuss the evolution of the inaugural Enhancing Student Learning through Innovative Scholarship conference, of which this volume contains contributed papers. This conference, the first national meeting open to all teaching (as opposed to research) focussed academic took place in Durham in July 2015

    Anesthesia Preoperative Clinic Referral for Elevated Hba1c Reduces Complication Rate in Diabetic Patients Undergoing Total Joint Arthroplasty

    Get PDF
    Background: Diabetes mellitus (DM) is risk factor for complications after orthopedic surgery. Objectives: We tested the hypothesis that anesthesia preoperative clinic (APC) referral for elevated glycosylated hemoglobin (HbA1c) reduces complication rate after total joint arthroplasty (TJA). Patients and Methods: Patients (n = 203) with and without DM were chosen from 1,237 patients undergoing TJA during 2006 - 12. Patients evaluated in the APC had surgery in 2006 - 8 regardless of HbA1c (uncontrolled). Those evaluated between in subsequent two-year intervals were referred to primary care for HbA1c ≥ 10% and ≥ 8%, respectively, to improve DM control before surgery. Complications and mortality were quantified postoperatively and at three, six, and twelve months. Length of stay (LOS) and patients requiring a prolonged LOS (\u3e 5 days) were recorded. Results: Patients (197 men, 6 women) underwent 71, 131, and 1 total hip, knee, and shoulder replacements, respectively. Patients undergoing TJA with uncontrolled HbA1c and those with HbA1c \u3c 10%, but not those with HbA1c \u3c 8%, had a higher incidence of coronary disease and hypercholesterolemia than patients without DM. An increase in complication rate was observed in DM patients with uncontrolled HbA1c versus patients without DM (P \u3c 0.001); the complication rate progressively decreased with tighter HbA1c control. More DM patients with preoperative HbA1c that was uncontrolled or ≥ 10% required prolonged LOS versus those without DM (P \u3c 0.001 and P = 0.0404, respectively). Conclusions: APC referral for elevated HbA1c reduces complication rate and the incidence of prolonged hospitalization during the first year after surgery in diabetics undergoing TJA
    • …
    corecore