468 research outputs found

    Berlin, die Stadt der Hohenzollern

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    BERLIN, DIE STADT DER HOHENZOLLERN Berlin, die Stadt der Hohenzollern / Wolff, Fritz (Public Domain) ( - ) Cover front ( - ) Title page ( - ) Hochgeehrte Fest-Versammlung! ( - ) Cover back ( - ) ColorChart ( -

    Spectral and Timing Analysis of the accretion-powered pulsar 4U 1626-67 observed with Suzaku and NuSTAR

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    We present an analysis of the spectral shape and pulse profile of the accretion-powered pulsar 4U 1626-67 observed with Suzaku and NuSTAR during a spin-up state. The pulsar, which experienced a torque reversal to spin-up in 2008, has a spin period of 7.7 s. Comparing the phase-averaged spectra obtained with Suzaku in 2010 and with NuSTAR in 2015, we find that the spectral shape changed between the two observations: the 3-10 keV flux increased by 5% while the 30-60 keV flux decreased significantly by 35%. Phase-averaged and phase-resolved spectral analysis shows that the continuum spectrum observed by NuSTAR is well described by an empirical NPEX continuum with an added broad Gaussian emission component around the spectral peak at 20 keV. Taken together with the observed Pdot value obtained from Fermi/GBM, we conclude that the spectral change between the Suzaku and NuSTAR observations was likely caused by an increase of the accretion rate. We also report the possible detection of asymmetry in the profile of the fundamental cyclotron line. Furthermore, we present a study of the energy-resolved pulse profiles using a new relativistic ray tracing code, where we perform a simultaneous fit to the pulse profiles assuming a two-column geometry with a mixed pencil- and fan-beam emission pattern. The resulting pulse profile decompositions enable us to obtain geometrical parameters of accretion columns (inclination, azimuthal and polar angles) and a fiducial set of beam patterns. This information is important to validate the theoretical predictions from radiation transfer in a strong magnetic field.Comment: 19 pages, 14 figures, Accepted for publication in ApJ on May 5, 201

    USA and RXTE Observations of a Variable Low-Frequency QPO in XTE J1118+480

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    The USA experiment on ARGOS and RXTE have exensively observed the X-ray transient XTE J1118+480 during its recent outburst in 2000 April--June. We present detailed monitoring of the evolution of a low frequency QPO which drifts from 0.07 Hz to 0.15 Hz during the outburst. We examine possible correlations of the QPO frequency with the flux and spectral characteristics of the source, and compare this QPO to low frequency QPOs observed in other black hole candidates.Comment: Accepted by ApJ Letters, reference added, minor revisions, 6 page

    USA Observation of Spectral and Timing Evolution During the 2000 Outburst of XTE J1550-564

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    We report on timing and spectral observations of the 2000 outburst of XTE J1550-564 made by the Unconventional Stellar Aspect (USA) Experiment on board the Advanced Research and Global Observation Satellite (ARGOS). We observe a low-frequency quasi-periodic oscillation (LFQPO) with a centroid frequency that tends to increase with increasing flux and a fractional rms amplitude which is correlated with the hardness ratio. The evolution of the hardness ratio (4--16 keV/1--4 keV) with time and source flux is examined. The hardness-intensity diagram (HID) shows a cyclical movement in the clockwise direction and possibly indicates the presence of two independent accretion flows. We observe a relationship between the USA 4--16 keV count rate and radio observations and discuss this in the context of previously observed correlations between X-ray, radio, optical and IR data. We examine our results in the context of models invoking two accretion flows: a thin disk and a hot sub-Keplerian flow.Comment: 11 pages, 2 figure

    Определение содержания нефтепродуктов и продуктов сгорания угля в воде и донных отложениях реки Томь

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    Почвенный покров и водоемы - основные ресурсы жизнедеятельности человека - в первую очередь страдают от химических загрязнений, поэтому их состояние очень важно для характеристики природной среды.Soil and water - the basic resources of human life - the first to suffer from chemical pollution, so their status is very important for the characteristics of the natural environment

    Multidimensional screening for predicting pain problems in adults : a systematic review of screening tools and validation studies

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    Screening tools allowing to predict poor pain outcomes are widely used. Often these screening tools contain psychosocial risk factors. This review (1) identifies multidimensional screening tools that include psychosocial risk factors for the development or maintenance of pain, pain-related distress, and pain-related disability across pain problems in adults, (2) evaluates the quality of the validation studies using Prediction model Risk Of Bias ASsessment Tool (PROBAST), and (3) synthesizes methodological concerns. We identified 32 articles, across 42 study samples, validating 7 screening tools. All tools were developed in the context of musculoskeletal pain, most often back pain, and aimed to predict the maintenance of pain or pain-related disability, not pain-related distress. Although more recent studies design, conduct, analyze, and report according to best practices in prognosis research, risk of bias was most often moderate. Common methodological concerns were identified, related to participant selection (eg, mixed populations), predictors (eg, predictors were administered differently to predictors in the development study), outcomes (eg, overlap between predictors and outcomes), sample size and participant flow (eg, unknown or inappropriate handling of missing data), and analysis (eg, wide variety of performance measures). Recommendations for future research are provided

    Underutilization of information and knowledge in everyday medical practice: Evaluation of a computer-based solution

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    <p>Abstract</p> <p>Background</p> <p>The medical history is acknowledged as the <it>sine qua non </it>for quality medical care because recognizing problems is pre-requisite for managing them. Medical histories typically are incomplete and inaccurate, however. We show here that computers are a solution to this issue of information gathering about patients. Computers can be programmed to acquire more complete medical histories with greater detail across a range of acute and chronic issues than physician histories.</p> <p>Methods</p> <p>Histories were acquired by physicians in the usual way and by a computer program interacting directly with patients. Decision-making of what medical issues were queried by computer were made internally by the software, including determination of the chief complaint. The selection of patients was from admissions to the Robert-Bosch-Hospital, Stuttgart, Germany by convenience sampling. Physician-acquired and computer-acquired histories were compared on a patient-by-patient basis for 45 patients.</p> <p>Results</p> <p>The computer histories reported 160 problems not recorded in physician histories or slightly more than 3.5 problems per patient. However, physicians but not the computer reported 13 problems. The data show that computer histories reported problems across a range of organ systems, that the problems detected by computer but not physician histories were both acute and chronic and that the computer histories detected a significant number of issues important for preventing further morbidity.</p> <p>Conclusion</p> <p>A combination of physician and computer-acquired histories, in non-emergent situations, with the latter available to the physician at the time he or she sees the patient, is a far superior method for collecting historical data than the physician interview alone.</p
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