2,361 research outputs found

    No evidence for an early seventeenth-century Indian sighting of Keplers supernova (SN1604)

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    In a recent paper Sule et al. (Astronomical Notes, vol. 332 (2011), 655) argued that an early 17th-century Indian mural of the constellation Sagittarius with a dragon-headed tail indicated that the bright supernova of 1604 was also sighted by Indian astronomers. In this paper it will be shown that this identification is based on a misunderstanding of traditional Islamic astrological iconography and that the claim that the mural represents an early 17th-century Indian sighting of the supernova of 1604 has to be rejected.Comment: 7 pages, 6 figures. To appear in Astronomical Notes, vol. 334, issue 5 (2013), DOI number 1172

    Three editions of the Star Catalogue of Tycho Brahe

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    Tycho Brahe completed his catalogue with the positions and magnitudes of 1004 fixed stars in 1598. This catalogue circulated in manuscript form. Brahe edited a shorter version with 777 stars, printed in 1602, and Kepler edited the full catalogue of 1004 stars, printed in 1627. We provide machine-readable versions of the three versions of the catalogue, describe the differences between them and briefly discuss their accuracy on the basis of comparison with modern data from the Hipparcos Catalogue. We also compare our results with earlier analyses by Dreyer (1916) and Rawlins (1993), finding good overall agreement. The magnitudes given by Brahe correlate well with modern values, his longitudes and latitudes have error distributions with widths of about 2 arcmin, with excess numbers of stars with larger errors (as compared to Gaussian distributions), in particular for the faintest stars. Errors in positions larger than 10 arcmin, which comprise about 15 per cent of the entries, are likely due to computing or copying errors.Comment: Accepted by Astronomy and Astrophysics; 24 pages; 63 figures; 3 machine readable tables made available at CD

    The Star Catalogue of Hevelius

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    The catalogue by Johannes Hevelius with the positions and magnitudes of 1564 entries was published by his wife Elisabeth Koopman in 1690. We provide a machine-readable version of the catalogue, and briefly discuss its accuracy on the basis of comparison with data from the modern Hipparcos Catalogue. We compare our results with an earlier analysis by Rybka (1984), finding good overall agreement. The magnitudes given by Hevelius correlate well with modern values. The accuracy of his position measurements is similar to that of Brahe, with sigma=2 arcmin for with more errors larger than 5 arcmin than expected for a Gaussian distribution. The position accuracy decreases slowly with magnitude. The fraction of stars with position errors larger than a degree is 1.5 per cent, rather smaller than the fraction of 5 per cent in the star catalogue of Brahe.Comment: Accepted by Astronomy and Astrophysics; 23 pages; 62 figures; 1 table made accessible via CD

    Early star catalogues of the southern sky: De Houtman, Kepler (Second and Third Classes), and Halley

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    De Houtman in 1603, Kepler in 1627 and Halley in 1679 published the earliest modern catalogues of the southern sky. We provide machine-readable versions of these catalogues, make some comparisons between them, and briefly discuss their accuracy on the basis of comparison with data from the modern Hipparcos Catalogue. We also compare our results for De Houtman with those by Knobel (1917) finding good overall agreement. About half of the about 200 new stars (with respect to Ptolemaios) added by De Houtman are in twelve new constellations, half in old constellations like Centaurus, Lupus and Argo. The right ascensions and declinations given by De Houtman have error distributions with widths of about 40 arcmin, the longitudes and latitudes given by Kepler have error distributions with widths of about 45 arcmin. Halley improves on this by more than an order of magnitude to widths of about 3 arcmin, and all entries in his catalogue can be identified. The measurement errors of Halley are due to a systematic deviation of his sextant (increasing with angle to 2 arcmin at 60 degrees) and random errors of 0.7 arcmin. The position errors in the catalogue of Halley are dominated by the position errors in the reference stars, which he took from Brahe.Comment: 26 pages, 58 figures. Tables will become available at CDS once the article appears in Astronomy and Astrophysic

    Number Partitioning on a Quantum Computer

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    We present an algorithm to compute the number of solutions of the (constrained) number partitioning problem. A concrete implementation of the algorithm on an Ising-type quantum computer is given.Comment: 5 pages, 1 figure, see also http://rugth30.phys.rug.nl/compphys/qce.ht

    Surface plasmon resonance immunosensors: sensitivity considerations

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    Some aspects of improving surface plasmon resonance response in immunosensing applications are considered. Both from calculations and experiments, it was found that maximum sensitivity is obtained for a silver layer about 55 nm thick in direct contact with the species to be quantified. Application of an intermediate layer with high permittivity can be useful in suppressing background responses. Experimentally, a protein surface-coverage fraction of ca. 0.1 could be measured, corresponding to ca. 10−10 mol1−1 antibody

    Sputum Induction in Children Is Feasible and Useful in a Bustling General Hospital Practice

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    The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The Jeroen Bosch Hospital funded this study.Peer reviewedPublisher PD

    Complications in subfascial endoscopic perforating vein surgery: A report of two cases

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    AbstractSubfascial endoscopic perforating vein surgery is a safe method for the division of incompetent perforating veins. Nevertheless, we report two cases with unfortunate complications: the posterior tibial artery and tibial nerve were damaged during the procedures. In one patient this resulted in a reintervention, but in both patients it resulted in permanent discomfort. We then present a guideline that may prevent damage to these critical structures. (J Vasc Surg 2001;33:1108-10.

    Child protection outcomes of the Australian Nurse Family Partnership Program for Aboriginal infants and their mothers in Central Australia

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    © 2018 Segal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background The Nurse Family Partnership Program developed in the USA, designed to improve mother and infant/child outcomes, has reported lower rates of child protection system involvement. The study tested the hypothesis that an adapted Nurse Family Partnership Program implemented in an Aboriginal community in Central Australia (the FPP) would improve Child Protection outcomes. Methods This was a retrospective and prospective cohort study drawing on linked administrative data, including birth registry, primary health care client information system, FPP program data, and child protection data. Participants were children of women eligible for the FPP program (an exposed and a control group of women, eligible but not referred) live-born between 1/3/2009 (program commencement) and 31/12/2015. Child protection data covered all reports, investigations, substantiations and out-of-home care placements from the time of the child’s birth to 31/12/2016. Generalised linear modelling was used to estimate the relative risk (RR) of involvement with child protection and type of involvement (report, investigation, substantiation, out-of-home-care placement) among FPP and control children. Results FPP mothers (n = 291) were on average younger, were more likely to be first-time mothers and experiencing housing instability than control mothers (n = 563). Among younger mothers 20 years, FPP children had statistically significantly lower rates of involvement with child protection (ARRreport = 0.49, 95% CI: 0.29 to 0.82; ARRinvestigation = 0.34, 95% CI: 0.19 to 0.64; ARRsubstantiation = 0.45, 95% CI: 0.21 to 0.96) and experience fewer days in care (ARR = 0.10, 95% CI: 0.02 to 0.48). Among children of first-time mothers, FPP children also had statistically significantly lower rates of involvement with child protection (ARRreport = 0.50, 95% CI: 0.30 to 0.83; ARRinvestigation = 0.36, 95% CI: 0.19 to 0.67; ARRsubstantiation = 0.38, 95% CI: 0.18 to 0.80) and fewer days in care (ARR = 0.06, 95% CI: 0.01 to 0.27). Conclusion Study results suggest a modified Nurse Family Partnership delivered by an Indigenous community-controlled organisation may have reduced child protection system involvement in a highly vulnerable First Nations population, especially in younger or first-time mothers. Testing these results with an RCT design is desirable

    Random Costs in Combinatorial Optimization

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    The random cost problem is the problem of finding the minimum in an exponentially long list of random numbers. By definition, this problem cannot be solved faster than by exhaustive search. It is shown that a classical NP-hard optimization problem, number partitioning, is essentially equivalent to the random cost problem. This explains the bad performance of heuristic approaches to the number partitioning problem and allows us to calculate the probability distributions of the optimum and sub-optimum costs.Comment: 4 pages, Revtex, 2 figures (eps), submitted to PR
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