3,091 research outputs found

    The Hot Interstellar Medium in Normal Elliptical Galaxies III: The Thermal Structure of the Gas

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    This is the third paper in a series analyzing X-ray emission from the hot interstellar medium in a sample of 54 normal elliptical galaxies observed by Chandra, focusing on 36 galaxies with sufficient signal to compute radial temperature profiles. We distinguish four qualitatively different types of profile: positive gradient (outwardly rising), negative gradients (falling), quasi-isothermal (flat) and hybrid (falling at small radii, then rising). We measure the mean logarithmic temperature gradients in two radial regions: from 0--2 JJ-band effective radii RJR_J (excluding the central point source), and from 2--4RJ4R_J. We find the outer gradient to be uncorrelated with intrinsic host galaxy properties, but strongly influenced by the environment: galaxies in low-density environments tend to show negative outer gradients, while those in high-density environments show positive outer gradients, suggesting influence of circumgalactic hot gas. The inner temperature gradient is unaffected by the environment but strongly correlated with intrinsic host galaxy characteristics: negative inner gradients are more common for smaller, optically faint, low radio-luminosity galaxies, whereas positive gradients are found in bright galaxies with stronger radio sources. There is no evidence for bimodality in the distribution of inner or outer gradients. We propose three scenarios to explain the inner temperature gradients: (1) Weak AGN heat the ISM locally, higher-luminosity AGN heat the system globally through jets inflating cavities at larger radii; (2) The onset of negative inner gradients indicates a declining importance of AGN heating relative to other sources, such as compressional heating or supernovae; (3) The variety of temperature profiles are snapshots of different stages of a time-dependent flow.Comment: 18 pages, emulateapj, 55 figures (36 online-only figures included in astro-ph version), submitted to Ap

    Infrared Magnitude-Redshift Relations for Luminous Radio Galaxies

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    Infrared magnitude-redshift relations for the 3CR and 6C samples of radio galaxies are presented for a wide range of plausible cosmological models, including those with non-zero cosmological constant OmegaLambda. Variations in the galaxy formation redshift, metallicity and star formation history are also considered. The results of the modelling are displayed in terms of magnitude differences between the models and no-evolution tracks, illustrating the amount of K-band evolution necessary to account for the observational data. Given a number of plausible assumptions, the results of these analyses suggest that: (i) cosmologies which predict T_0xH_0>1 (where T_0 denotes the current age of the universe) can be excluded; (ii) the star formation redshift should lie in the redshift interval 5<z<20, values towards the lower end of the range being preferred in cosmologies with larger values of T_0xH_0; (iii) the Einstein-de Sitter model provides a reasonable fit to the data; (iv) models with finite values of OmegaLambda can provide good agreement with the observations only if appropriate adjustments of other parameters such as the galaxy metallicities and star-formation histories are made. Without such modifications, even after accounting for stellar evolution, the high redshift radio galaxies are more luminous (ie. more massive) than those nearby in models with finite OmegaLambda, including the favoured model with Omega=0.3, OmegaLambda=0.7. For cosmological models with larger values of T_0xH_0, the conclusions are the same regardless of whether any adjustments are made or not. The implications of these results for cosmology and models of galaxy formation are discussed.Comment: 14 pages, LaTeX, 9 figures, accepted for publication in MNRAS. Replacement corrects some annoying typo

    Definition of whole person care in general practice in the English language literature: A systematic review

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    Objectives: The importance of ‘whole person’ or ‘holistic’ care is widely recognised, particularly with an increasing prevalence of chronic multimorbidity internationally. This approach to care is a defining feature of general practice. However, its precise meaning remains ambiguous. We aimed to determine how the term ‘whole person’ care is understood by general practitioners (GPs), and whether it is synonymous with ‘[w]holistic’ and ‘biopsychosocial’ care. Design: Systematic literature review. Methods: MEDLINE, PubMed, EMBASE, CINAHL, PsycINFO, Web of Science, Proquest Dissertations and Theses, Science. gov (Health and Medicine database), Google Scholar and included studies’ reference lists were searched with an unlimited date range. Systematic or literature reviews, original research, theoretical articles or books/book chapters; specific to general practice; relevant to the research question; and published in English were included. Included literature was critically appraised, and data were extracted and analysed using thematic synthesis. Results: Fifty publications were included from 4297 non-duplicate records retrieved. Six themes were identified: a multidimensional, integrated approach; the importance of the therapeutic relationship; acknowledging doctors’ humanity; recognising patients’ individual personhood; viewing health as more than absence of disease; and employing a range of treatment modalities. Whole person, biopsychosocial and holistic terminology were often used interchangeably, but were not synonymous. Conclusions: Whole person, holistic and biopsychosocial terminology are primarily characterised by a multidimensional approach to care and incorporate additional elements described above. Whole person care probably represents the closest representation of the basis for general practice. Health systems aiming to provide whole person care need to address the challenge of integrating the care of other health professionals, and maintaining the patient–doctor relationship central to the themes identified. Further research is required to clarify the representativeness of the findings, and the relative importance GPs’ assign to each theme. PROSPERO registration number: CRD42017058824

    The STATs in cell stress-type responses

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    In the early 1990's, a new cell signaling pathway was described. This new paradigm, now known as the JAK/STAT pathway, has been extensively investigated in immune-type cells in response to interferons and interleukins. However, recent evidence suggests that the JAK/STAT pathway also mediates diverse cellular responses to various forms of biological stress including hypoxia/reperfusion, endotoxin, ultraviolet light, and hyperosmolarity. The current literature describing the JAK/STAT pathway's role in cellular stress responses has been reviewed herein, but it is clear that our knowledge in this area is far from complete

    S4_3 Dome Sweet Dome

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    In the instant classic ‘The Simpsons Movie’ the town of Springfield becomes trapped by a massive glass dome. We calculated that the residents of Springfield have at the most 28 hours to escape the dome before they suffocate to death.

    Vietnam's coffee export industry : an analysis of the potential long-term macroeconomic impacts

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    1 online resource (57 p.) : ill. (chiefly col.)Includes abstract.Includes bibliographical references (p. 56-57).Coffee, as a globally traded primary commodity, has historically been and continues to be one of the most valuable economic resources that is exported from the Global South. Vietnam has become the second largest and one of the fastest growing coffee exporters in the world all within a relatively short period of time. This particular export industry has expanded and developed to become an integral part of the Vietnamese national economy. The trajectory of Vietnam’s long-term macroeconomic development rests, to a large degree, on the future growth and direction in which this national industry pursues. This paper discusses and evaluates the degree to which Vietnam relies on coffee for its overall economic development as well as potential next steps for this particular industry to take in order to further guarantee it can continue to contribute to the long-term balanced and sustainable national macroeconomic development plans of the country

    The Humanist Ulrich von Hutten: A Reappraisal of his Humor

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    Ulrich von Hutten (1488-1523), Renaissance-Reformation publisher and ardent champion of German nationalism, has previously been characterized as a bitter and vehement political satirist. From this concise, critical survey of his comic writing a more balanced, congenial image of Hutten emerges

    S4_4 Roberto Carlos' 'Impossible' Free Kick

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    In the Tournoi de France 1997, Roberto Carlos scored a free kick in a 1-1 draw between France and Brazil. This goal would go on to make headlines and feature in highlight reels for many years to come. Our calculations show the force applied to the football by Carlos to be 320.2 N at an angle of 9.84 degrees from the initial direction of the ball

    Effect of low-intensity long-duration ultrasound on the symptomatic relief of knee osteoarthritis: a randomized, placebo-controlled double-blind study

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    Background: Wearable long-duration low-intensity ultrasound is an emerging non-invasive and non-narcotic therapy for the daily treatment of musculoskeletal pain. The aim of this randomized, double-blind, placebo-controlled study was to examine whether long-duration low-intensity ultrasound was effective in treating pain and improving function in patients with knee osteoarthritis. Methods: Ninety patients with moderate to severe knee pain and radiographically confirmed knee osteoarthritis (Kellgren-Lawrence grade I/II) were randomized for treatment with active (n = 55) or placebo (n = 35) devices applied daily to the treated knee. Investigators and subjects were blinded to treatment groups. Ultrasound (3 MHz, 0.132 W/cm2, 1.3 W) was applied with a wearable device for 4 h daily for 6 weeks, delivering 18,720 J per treatment. The primary outcome was change in pain intensity (numeric rating scale) assessed prior to intervention (baseline) and after 6 weeks. Secondary outcomes of functional change were measured at baseline and after 6 weeks using the Western Ontario McMaster Osteoarthritis Questionnaire (n = 84), along with range of motion (flexion, extension) and isometric muscle strength (flexion, extension and rotation) tests on the injured knee in a small pilot subset (n =17). Results: The study had a 93% retention rate, and there were no significant differences between the groups regarding demographic variables or baseline outcome measures. Patients treated with active therapy observed a significant mean NRS pain reduction over the 6-week study of 1.96 points for active (p \u3c 0.0001), compared with a 0.85 points reduction for placebo (p = 0.13). The functional score was also significantly improved by 505 points for the active group over the 311-point improvement for placebo group compared to baseline (p = 0.02). In the pilot subset evaluated, rotational strength increased from baseline to 6 weeks (3.2 N, p = 0.03); however, no other measures were significant. Conclusions: Long-duration low-intensity ultrasound significantly reduced pain and improved joint function in patients with moderate to severe osteoarthritis knee pain. The clinical findings suggest that ultrasound may be used as a conservative non-pharmaceutical and non-invasive treatment option for patients with knee osteoarthritis. Additional research is warranted on non-weight bearing joints of the musculoskeletal system as well as extended treatment time frames and follow-up. Trial registration: NCT02083861, registered 11 March 2014, https://clinicaltrials.gov/ct2/show/results/NCT0208386

    Top fuel dragster powertrain modelling

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    Here we consider the construction of a model in the matlab/simulink environment that describes the dynamic processes occurring within the driveline of a Top Fuel Dragster. Particular emphasis is placed upon development of the model for aspects of powertrain performance that are unique to operation of a dragster. This includes clutch operation, tyre modelling including squat and growth and vertical load variation. The model predictions are compared to vehicle test data, and although predictions are not accurate clear similarities are seen. Hence a good basis for simulating the dragster has been produced but significant parameter tuning work is still required. The paper considers future enhancements to the model and methods for identifying model parameters, in order to further improve accuracy
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