869 research outputs found

    Last mile cold chain distribution challenges for privately-owned and retail pharmacies in Auckland Park and surrounding areas, Johannesburg

    Get PDF
    Abstract: Research objective: The primary research objective was to determine the challenges prevailing in the last mile distribution of cold chain medication to privately-owned and retail pharmacies in Auckland Park and surrounding areas. Methodology: A positivist research philosophy guided a descriptive quantitative survey design. Structured questionnaires were hand-delivered to all 43 privately-owned and retail pharmacies in the Auckland Park and surrounding areas. Findings: Some discrepancies were found in the cold chain distribution process that could compromise the quality of the cold chain medication. Although these pharmacies mostly used the correct storage systems for cold chain medication within the specified temperature range, the appropriate mode of transportation for delivery to the pharmacy is questionable..

    How do methanol masers manage to appear in the youngest star vicinities and isolated molecular clumps?

    Full text link
    General characteristics of methanol (CH3OH) maser emission are summarized. It is shown that methanol maser sources are concentrated in the spiral arms. Most of the methanol maser sources from the Perseus arm are associated with embedded stellar clusters and a considerable portion is situated close to compact HII regions. Almost 1/3 of the Perseus Arm sources lie at the edges of optically identified HII regions which means that massive star formation in the Perseus Arm is to a great extent triggered by local phenomena. A multiline analysis of the methanol masers allows us to determine the physical parameters in the regions of maser formation. Maser modelling shows that class II methanol masers can be pumped by the radiation of the warm dust as well as by free-free emission of a hypercompact region hcHII with a turnover frequency exceeding 100 GHz. Methanol masers of both classes can reside in the vicinity of hcHIIs. Modelling shows that periodic changes of maser fluxes can be reproduced by variations of the dust temperature by a few percent which may be caused by variations in the brightness of the central young stellar object reflecting the character of the accretion process. Sensitive observations have shown that the masers with low flux densities can still have considerable amplification factors. The analysis of class I maser surveys allows us to identify four distinct regimes that differ by the series of their brightest lines.Comment: 8 pages, 4 figures, invited presentation at IAU242 "Astrophysical Masers and their environments

    Time evolution of the Rabi Hamiltonian from the unexcited vacuum

    Full text link
    The Rabi Hamiltonian describes a single mode of electromagnetic radiation interacting with a two-level atom. Using the coupled cluster method, we investigate the time evolution of this system from an initially empty field mode and an unexcited atom. We give results for the atomic inversion and field occupation, and find that the virtual processes cause the field to be squeezed. No anti-bunching occurs.Comment: 25 pages, 8 figures, RevTe

    Polarized point sources in the LOFAR Two-meter Sky Survey: A preliminary catalog

    Get PDF
    The polarization properties of radio sources at very low frequencies (h45m–15h30m right ascension, 45°–57° declination, 570 square degrees). We have produced a catalog of 92 polarized radio sources at 150 MHz at 4.′3 resolution and 1 mJy rms sensitivity, which is the largest catalog of polarized sources at such low frequencies. We estimate a lower limit to the polarized source surface density at 150 MHz, with our resolution and sensitivity, of 1 source per 6.2 square degrees. We find that our Faraday depth measurements are in agreement with previous measurements and have significantly smaller errors. Most of our sources show significant depolarization compared to 1.4 GHz, but there is a small population of sources with low depolarization indicating that their polarized emission is highly localized in Faraday depth. We predict that an extension of this work to the full LOTSS data would detect at least 3400 polarized sources using the same methods, and probably considerably more with improved data processing

    The utilisation of health research in policy-making: Concepts, examples and methods of assessment

    Get PDF
    The importance of health research utilisation in policy-making, and of understanding the mechanisms involved, is increasingly recognised. Recent reports calling for more resources to improve health in developing countries, and global pressures for accountability, draw greater attention to research-informed policy-making. Key utilisation issues have been described for at least twenty years, but the growing focus on health research systems creates additional dimensions. The utilisation of health research in policy-making should contribute to policies that may eventually lead to desired outcomes, including health gains. In this article, exploration of these issues is combined with a review of various forms of policy-making. When this is linked to analysis of different types of health research, it assists in building a comprehensive account of the diverse meanings of research utilisation. Previous studies report methods and conceptual frameworks that have been applied, if with varying degrees of success, to record utilisation in policy-making. These studies reveal various examples of research impact within a general picture of underutilisation. Factors potentially enhancing utilisation can be identified by exploration of: priority setting; activities of the health research system at the interface between research and policy-making; and the role of the recipients, or 'receptors', of health research. An interfaces and receptors model provides a framework for analysis. Recommendations about possible methods for assessing health research utilisation follow identification of the purposes of such assessments. Our conclusion is that research utilisation can be better understood, and enhanced, by developing assessment methods informed by conceptual analysis and review of previous studies

    A pathway to a stronger research culture in health policy

    Get PDF
    There are currently limited pathways into a career in health policy research in Australia, due in part to a serious absence of health policy research capability in Australian universities. The authors define what they consider health policy research and education should comprise, then examine what is currently on offer and propose ways to strengthen health policy research in Australia. This paper, which is part analysis and part commentary, is offered to provoke wider debate about how health policy research can be nurtured in Australia

    Detailed spectral and morphological analysis of the shell type SNR RCW 86

    Full text link
    Aims: We aim for an understanding of the morphological and spectral properties of the supernova remnant RCW~86 and for insights into the production mechanism leading to the RCW~86 very high-energy gamma-ray emission. Methods: We analyzed High Energy Spectroscopic System data that had increased sensitivity compared to the observations presented in the RCW~86 H.E.S.S. discovery publication. Studies of the morphological correlation between the 0.5-1~keV X-ray band, the 2-5~keV X-ray band, radio, and gamma-ray emissions have been performed as well as broadband modeling of the spectral energy distribution with two different emission models. Results:We present the first conclusive evidence that the TeV gamma-ray emission region is shell-like based on our morphological studies. The comparison with 2-5~keV X-ray data reveals a correlation with the 0.4-50~TeV gamma-ray emission.The spectrum of RCW~86 is best described by a power law with an exponential cutoff at Ecut=(3.5±1.2stat)E_{cut}=(3.5\pm 1.2_{stat}) TeV and a spectral index of Γ\Gamma~1.6±0.21.6\pm 0.2. A static leptonic one-zone model adequately describes the measured spectral energy distribution of RCW~86, with the resultant total kinetic energy of the electrons above 1 GeV being equivalent to \sim0.1\% of the initial kinetic energy of a Type I a supernova explosion. When using a hadronic model, a magnetic field of BB~100μ\muG is needed to represent the measured data. Although this is comparable to formerly published estimates, a standard E2^{-2} spectrum for the proton distribution cannot describe the gamma-ray data. Instead, a spectral index of Γp\Gamma_p~1.7 would be required, which implies that ~7×1049/ncm37\times 10^{49}/n_{cm^{-3}}erg has been transferred into high-energy protons with the effective density ncm3=n/1n_{cm^{-3}}=n/ 1 cm^-3. This is about 10\% of the kinetic energy of a typical Type Ia supernova under the assumption of a density of 1~cm^-3.Comment: accepted for publication by A&

    Multiple Sclerosis Susceptibility-Associated SNPs Do Not Influence Disease Severity Measures in a Cohort of Australian MS Patients

    Get PDF
    Recent association studies in multiple sclerosis (MS) have identified and replicated several single nucleotide polymorphism (SNP) susceptibility loci including CLEC16A, IL2RA, IL7R, RPL5, CD58, CD40 and chromosome 12q13–14 in addition to the well established allele HLA-DR15. There is potential that these genetic susceptibility factors could also modulate MS disease severity, as demonstrated previously for the MS risk allele HLA-DR15. We investigated this hypothesis in a cohort of 1006 well characterised MS patients from South-Eastern Australia. We tested the MS-associated SNPs for association with five measures of disease severity incorporating disability, age of onset, cognition and brain atrophy. We observed trends towards association between the RPL5 risk SNP and time between first demyelinating event and relapse, and between the CD40 risk SNP and symbol digit test score. No associations were significant after correction for multiple testing. We found no evidence for the hypothesis that these new MS disease risk-associated SNPs influence disease severity
    corecore