32,768 research outputs found

    Fiscal year 1979 scientific and technical reports, articles, papers and presentations

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    This bibliography lists approximately 590 formal NASA technical reports, papers published in technical journals, presentations by MSFC personnel, and reports of MSFC contractors introduced into the NASA scientific and technical information system in 1979

    MCMC methods for functions modifying old algorithms to make\ud them faster

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    Many problems arising in applications result in the need\ud to probe a probability distribution for functions. Examples include Bayesian nonparametric statistics and conditioned diffusion processes. Standard MCMC algorithms typically become arbitrarily slow under the mesh refinement dictated by nonparametric description of the unknown function. We describe an approach to modifying a whole range of MCMC methods which ensures that their speed of convergence is robust under mesh refinement. In the applications of interest the data is often sparse and the prior specification is an essential part of the overall modeling strategy. The algorithmic approach that we describe is applicable whenever the desired probability measure has density with respect to a Gaussian process or Gaussian random field prior, and to some useful non-Gaussian priors constructed through random truncation. Applications are shown in density estimation, data assimilation in fluid mechanics, subsurface geophysics and image registration. The key design principle is to formulate the MCMC method for functions. This leads to algorithms which can be implemented via minor modification of existing algorithms, yet which show enormous speed-up on a wide range of applied problems

    Fiscal year 1977 scientific and technical reports, articles, papers, and presentations

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    This bibliography lists 78 NASA technical memoranda, notes, papers, and reports presented by Marshall Space Flight Center personnel in FY 1977. In addition, 525 papers by contractors to that facility are cited along with 129 papers cleared for presentation

    FY 1978 scientific and technical reports, articles, papers, and presentations

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    Abstracts of 73 technical papers published or presented by MSFC personnel in FY-78 are presented. In addition, over 400 papers by contractors to that facility are listed along with the STAR document number for each report. Titles of 208 additional papers already cleared for publication are included

    Geothermal studies - Yellowstone National Park /test site 11/, Wyoming

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    Summary report of diamond drilling in thermal areas of Yellowstone National Park, and method for determining heat flow in thermal area

    An Online Educational Program Improves Pediatric Oncology Nurses’ Knowledge, Attitudes, and Spiritual Care Competence

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    This study evaluated the potential impact of an online spiritual care educational program on pediatric nurses’ attitudes toward and knowledge of spiritual care and their competence to provide spiritual care to children with cancer at the end of life. It was hypothesized that the intervention would increase nurses’ positive attitudes toward and knowledge of spiritual care and increase nurses’ level of perceived spiritual care competence. A positive correlation was expected between change in nurses’ perceived attitudes toward and knowledge of spiritual care and change in nurses’ perceived spiritual care competence. A prospective, longitudinal design was employed, and analyses included one-way repeated-measures analysis of variance, linear regression, and partial correlation. Statistically significant differences were found in nurses’ attitudes toward and knowledge of spiritual care and nurses’ perceived spiritual care competence. There was a positive relationship between change scores in nurses’ attitudes toward and knowledge of spiritual care and nurses’ spiritual care competence. Online spiritual care educational programs may exert a lasting impact on nurses’ attitudes toward and knowledge of spiritual care and their competence to provide spiritual care to children with cancer at the end of life. Additional studies are required to evaluate the direct effects of educational interventions patient outcomes

    Notes and Comments

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    A Theoretical Model for the Mbh−σM_{\rm bh}-\sigma Relation for Supermassive Black Holes in Galaxies

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    We construct a model for the formation of black holes within galactic bulges. The initial state is a slowly rotating isothermal sphere, characterized by effective transport speed \aeff and rotation rate Ω\Omega. The black hole mass is determined when the centrifugal radius of the collapse flow exceeds the capture radius of the central black hole. This model reproduces the observed correlation between black hole masses and galactic velocity dispersions, \mbh \approx 10^8 M_\odot (\sigma/200 \kms)^4, where \sigma = \sqrt{2} \aeff. This model also predicts the ratio \mrat of black hole mass to host mass: \mrat ≈\approx 0.004 (\sigma/200 \kms).Comment: 9 pages, 2 figures, submitted to Astrophysical Journal Letter

    IPU or ITU? It all starts with PCT (palliative care training)

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    Background: Impending death is not well recognised. Due to improvements in technology and medicine, people are living longer with more complex health conditions and because of this, the death of a patient is an experience that many people entering a healthcare profession will have little of. As death occurs in any setting, at any time, it is vital that all healthcare professionals regardless of the setting they go on to work in, have adequate Palliative Care Training (PCT). / Aim: To understand what current training is available on the recognition of dying at undergraduate level. / Methods: An information gathering exercise of the following UK undergraduate courses: medicine, nursing, social work, physiotherapy, occupational therapy. All courses received an email asking what training was provided in recognising and communication of dying and what time was dedicated to this. / Results: 73/198 courses responded (37%). 18/20 medical courses provided training in recognising dying with a median of 2 hours dedicated, and 17/20 in the communication of dying with a median of 3 hours dedicated. 80% (43/54) of nursing and allied health professional courses provided some form of training in end-of-life care. Many of these courses expressed frustration at the lack of resources, funding, and time to include more training. Those with more time dedicated to PCT often had a ‘champion’ to advocate for it. / Conclusion: Training in end-of-life care was inconsistent and variable across courses and professions. Further work on how we can support the champions in progressing PCT input on the courses is needed

    Why Do Only Some Galaxy Clusters Have Cool Cores?

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    Flux-limited X-ray samples indicate that about half of rich galaxy clusters have cool cores. Why do only some clusters have cool cores while others do not? In this paper, cosmological N-body + Eulerian hydrodynamic simulations, including radiative cooling and heating, are used to address this question as we examine the formation and evolution of cool core (CC) and non-cool core (NCC) clusters. These adaptive mesh refinement simulations produce both CC and NCC clusters in the same volume. They have a peak resolution of 15.6 h^{-1} kpc within a (256 h^{-1} Mpc)^3 box. Our simulations suggest that there are important evolutionary differences between CC clusters and their NCC counterparts. Many of the numerical CC clusters accreted mass more slowly over time and grew enhanced cool cores via hierarchical mergers; when late major mergers occurred, the CC's survived the collisions. By contrast, NCC clusters experienced major mergers early in their evolution that destroyed embryonic cool cores and produced conditions that prevented CC re-formation. As a result, our simulations predict observationally testable distinctions in the properties of CC and NCC beyond the core regions in clusters. In particular, we find differences between CC versus NCC clusters in the shapes of X-ray surface brightness profiles, between the temperatures and hardness ratios beyond the cores, between the distribution of masses, and between their supercluster environs. It also appears that CC clusters are no closer to hydrostatic equilibrium than NCC clusters, an issue important for precision cosmology measurements.Comment: 17 emulateapj pages, 17 figures, replaced with version accepted to Ap
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