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114 results on '"Gray, R. C."'

1. Analysis of large-scale anisotropy of ultra-high energy cosmic rays in HiRes data

Author

Abbasi, R. U., Abu-Zayyad, T., Allen, M., Amann, J. F., Archbold, G., Belov, K., Belz, J. W., Bergman, D. R., Blake, S. A., Brusova, O. A., Burt, G. W., Cannon, C., Cao, Z., Deng, W., Fedorova, Y., Findlay, J., Finley, C. B., Gray, R. C., Hanlon, W. F., Hoffman, C. M., Holzscheiter, M. H., Hughes, G., Hüntemeyer, P., Ivanov, D., Jones, B. F, Jui, C. C. H., Kim, K., Kirn, M. A., Koers, H., Loh, E. C., Maestas, M. M., Manago, N., Marek, L. J., Martens, K., Matthews, J. A. J., Matthews, J. N., Moore, S. A., O'Neill, A., Painter, C. A., Perera, L., Reil, K., Riehle, R., Roberts, M. D., Rodriguez, D., Sasaki, M., Schnetzer, S. R., Scott, L. M., Sinnis, G., Smith, J. D., Sokolsky, P., Song, C., Springer, R. W., Stokes, B. T., Stratton, S. R., Thomas, J. R., Thomas, S. B., Thomson, G. B., Tinyakov, P., Tupa, D., Wiencke, L. R., Zech, A., and Zhang, X. more...

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Stereo data collected by the HiRes experiment over a six year period are examined for large-scale anisotropy related to the inhomogeneous distribution of matter in the nearby Universe. We consider the generic case of small cosmic-ray deflections and a large number of sources tracing the matter distribution. In this matter tracer model the expected cosmic ray flux depends essentially on a single free parameter, the typical deflection angle theta. We find that the HiRes data with threshold energies of 40 EeV and 57 EeV are incompatible with the matter tracer model at a 95% confidence level unless theta is larger than 10 degrees and are compatible with an isotropic flux. The data set above 10 EeV is compatible with both the matter tracer model and an isotropic flux., Comment: 9 pages, 5 Postscript figures more...

Published
2010
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2. Indications of Proton-Dominated Cosmic Ray Composition above 1.6 EeV

Author

Abbasi, R. U., Abu-Zayyad, T., Al-Seady, M., Allen, M., Amman, J. F., Anderson, R. J., Archbold, G., Belov, K., Belz, J. W., Bergman, D. R., Blake, S. A., Brusova, O. A., Burt, G. W., Cannon, C., Cao, Z., Deng, W., Fedorova, Y., Finley, C. B., Gray, R. C., Hanlon, W. F., Hoffman, C. M., Holzscheiter, M. H., Hughes, G., Huentemeyer, P., Jones, B. F, Jui, C. C. H., Kim, K., Kirn, M. A., Loh, E. C., Lundquist, J. P., Maestas, M. M., Manago, N., Marek, L. J., Martens, K., Matthews, J. A. J., Matthews, J. N., Moore, S. A., O'Neill, A., Painter, C. A., Perera, L., Reil, K., Riehle, R., Roberts, M., Rodriguez, D., Sasaki, N., Schnetzer, S. R., Scott, L. M., Sinnis, G., Smith, J. D., Sokolsky, P., Song, C., Springer, R. W., Stokes, B. T., Stratton, S., Thomas, S. B., Thomas, J. R., Thomson, G. B., Tupa, D., Zhang, X., and Zech, A. more...

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

We report studies of ultra-high energy cosmic ray composition via analysis of depth of airshower maximum (Xmax), for airshower events collected by the High Resolution Fly's Eye (HiRes) observatory. The HiRes data are consistent with a constant elongation rate d/d(log(E)) of 47.9 +- 6.0 (stat.) +- 3.2 (syst.)g/cm^2/decade for energies between 1.6 EeV and 63 EeV, and are consistent with a predominantly protonic composition of cosmic rays when interpreted via the QGSJET01 and QGSJET-II high-energy hadronic interaction models. These measurements constrain models in which the galactic-to-extragalactic transition is the cause of the energy spectrum "ankle' at 4 EeV., Comment: 11 pages, 4 figures, accepted for publication in Physical Review Letters more...

Published
2009
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3. Measurement of the Flux of Ultra High Energy Cosmic Rays by the Stereo Technique

Author

Abbasi, R. U., Abu-Zayyad, T., Al-Seady, M., Allen, M., Amann, J. F., Archbold, G., Belov, K., Belz, J. W., Bergman, D. R., Blake, S. A., Brusova, O. A., Burt, G. W., Cannon, C., Cao, Z., Deng, W., Fedorova, Y., Findlay, J., Finley, C. B., Gray, R. C., Hanlon, W. F., Hoffman, C. M., Holzscheiter, M. H., Hughes, G., Huntemeyer, P., Ivanov, D., Jones, B. F., Jui, C. C. H., Kim, K., Kirn, M. A., Loh, E. C., Maestas, M. M., Manago, N., Marek, L. J., Martens, K., Matthews, J. A. J., Matthews, J. N., Moore, S. A., O'Neil, A., Painter, C. A., Perera, L., Reil, K., Riehle, R., Roberts, M. D., Rodriguez, D., Sasaki, M., Schnetzer, S. R., Scott, L. M., Sinnis, G., Smith, J. D., Snow, R., Sokolsky, P., Springer, R. W., Stokes, B. T., Stratton, S. R., Thomas, J. R., Thomas, S. B., Thomson, G. B., Tupa, D., Wiencke, L. R., Zech, A., Zhang, B. K., Zhang, X., and Zhang, Y. more...

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Extragalactic Astrophysics
Abstract

The High Resolution Fly's Eye experiment has measured the flux of ultrahigh energy cosmic rays using the stereoscopic air fluorescence technique. The HiRes experiment consists of two detectors that observe cosmic ray showers via the fluorescence light they emit. HiRes data can be analyzed in monocular mode, where each detector is treated separately, or in stereoscopic mode where they are considered together. Using the monocular mode the HiRes collaboration measured the cosmic ray spectrum and made the first observation of the Greisen-Zatsepin-Kuzmin cutoff. In this paper we present the cosmic ray spectrum measured by the stereoscopic technique. Good agreement is found with the monocular spectrum in all details., Comment: 20 pages, 10 figures more...

Published
2009
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4. Search for Correlations between HiRes Stereo Events and Active Galactic Nuclei

Author

Abbasi, R. U., Abu-Zayyad, T., Allen, M., Amman, J. F., Archbold, G., Belov, K., Belz, J. W., BenZvi, S. Y., Bergman, D. R., Blake, S. A., Boyer, J. H., Brusova, O. A., Burt, G. W., Cannon, C., Cao, Z., Deng, W., Fedorova, Y., Findlay, J., Finley, C. B., Gray, R. C., Hanlon, W. F., Hoffman, C. M., Holzscheiter, M. H., Hughes, G., Huntemeyer, P., Ivanov, D., Jones, B. F, Jui, C. C. H., Kim, K., Kirn, M. A., Knapp, B. C., Loh, E. C., Maestas, M. M., Manago, N., Mannel, E. J., Marek, L. J., Martens, K., Matthews, J. N., Moore, S. A., O'Neill, A., Painter, C. A., Perera, L., Reil, K., Riehle, R., Roberts, M. D., Sasaki, D. Rodriguez N., Schnetzer, S. R., Scott, L. M., Seman, M., Sinnis, G., Smith, J. D., Snow, R., Sokolsky, P., Song, C., Springer, R. W., Stokes, B. T., Stratton, S. R., Thomas, J. R., Thomas, S. B., Thomson, G. B., Tupa, D., Wiencke, L. R., Zech, A., and Zhang, X. more...

Subjects
Astrophysics
Abstract

We have searched for correlations between the pointing directions of ultrahigh energy cosmic rays observed by the High Resolution Fly's Eye experiment and Active Galactic Nuclei (AGN) visible from its northern hemisphere location. No correlations, other than random correlations, have been found. We report our results using search parameters prescribed by the Pierre Auger collaboration. Using these parameters, the Auger collaboration concludes that a positive correlation exists for sources visible to their southern hemisphere location. We also describe results using two methods for determining the chance probability of correlations: one in which a hypothesis is formed from scanning one half of the data and tested on the second half, and another which involves a scan over the entire data set. The most significant correlation found occurred with a chance probability of 24%., Comment: 13 pages, 1 table, 5 figures more...

Published
2008
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5. An upper limit on the electron-neutrino flux from the HiRes detector

Author

Abbasi, R. U., Abu-Zayyad, T., Allen, M., Amann, J. F., Archbold, G., Belov, K., Belz, J. W., Zvi, S. Y. Ben, Bergman, D. R., Biesiadecka, A., Blake, S. A., Boyer, J. H., Brusova, O. A., Burt, G. W., Cannon, C., Cao, Z., Deng, W., Fedorova, Y., Findlay, J., Finley, C. B., Gray, R. C., Hanlon, W. F., Hoffman, C. M., Holzscheiter, M. H., Hughes, G., Huentemeyer, P., Ivanov, D., Jones, B. F, Jui, C. C. H., Kim, K., Kirn, M. A., Knapp, B. C., Loh, E. C., Maestas, M. M., Manago, N., Mannel, E. J., Marek, L. J., Martens, K., Matthews, J. A. J., Matthews, J. N., Moore, S. A., O'Neill, A., Painter, C. A., Perera, L., Reil, K., Riehle, R., Roberts, M. D., Rodriguez, D., Sasaki, M., Schnetzer, S. R., Scott, L. M., Seman, M., Sinnis, G., Smith, J. D., Snow, R., Sokolsky, P., Song, C., Springer, R. W., Stokes, B. T., Stratton, S. R., Thomas, J. R., Thomas, S. B., Thomson, G. B., Tupa, D., Wiencke, L. R., Zech, A., and Zhang, X. more...

Subjects
Astrophysics
Abstract

Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes) detector are very sensitive to upward-going, Earth-skimming ultrahigh energy electron-neutrino-induced showers. This is due to the relatively large interaction cross sections of these high-energy neutrinos and to the Landau-Pomeranchuk-Migdal (LPM) effect. The LPM effect causes a significant decrease in the cross sections for bremsstrahlung and pair production, allowing charged-current electron-neutrino-induced showers occurring deep in the Earth's crust to be detectable as they exit the Earth into the atmosphere. A search for upward-going neutrino-induced showers in the HiRes-II monocular dataset has yielded a null result. From an LPM calculation of the energy spectrum of charged particles as a function of primary energy and depth for electron-induced showers in rock, we calculate the shape of the resulting profile of these showers in air. We describe a full detector Monte Carlo simulation to determine the detector response to upward-going electron-neutrino-induced cascades and present an upper limit on the flux of electron-neutrinos., Comment: 13 pages, 3 figures. submitted to Astrophysical Journal more...

Published
2008
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6. Testing Cosmology at the ILC

Author

Birkedal, A., Matchev, K., Alexander, J., Ecklund, K., Fields, L., Gray, R. C., Hertz, D., Jones, C. D., and Pivarski, J.

Subjects
High Energy Physics - Phenomenology
Abstract

We investigate the capabilities for the LHC and the ILC to perform measurements of new physics parameters relevant for the calculation of the cosmological relic abundance of the lightest neutralino in supersymmetry. Specifically, we delineate the range of values for the cold dark matter relic abundance $\Omega_{\chi} h^2$, which will be consistent with the expected precision measurements at the LHC, and, subsequently, at the ILC. We illustrate our approach with a toy study of an "updated benchmark" point B'. We then show some preliminary results of a similar analysis along those lines of the LCC2 benchmark point in the focus point region., Comment: 6 pages, 4 figures. Based on talks given by A. Birkedal at Linear Collider workshops in 2004 and 2005 more...

Published
2005

10. Hospital Career Structure

Author

Appleyard, W. J., Barbor, P. R. H., Barraclough, M. A., Beeden, A. G., Berger, P., Black, A. J., Blaxill, R. W., Boggon, R. P., Butler, M. J., Chilvers, A. S., Church, Armorel B., Cobb, P. J., Cochrane, A. M. G., Condon, P. I., Cove-Smith, J. R., Cream, J. J., Croft, D. N., Crick, M. D. P., Davidson, N. McD., Davies, D. R., Davies, R. J., Devlin, H. B., Dutton, N. M., Eames, G. M., Eisinger, A. J., Eustace, P., Evans, D. S., Evans, J. M. G., Evans, R., Evans-Prosser, C. D. G., Eykyn, Susannah J., Fawcett, B. M., Foley, T. H., Follows, R. C., Frommer, D. J., Gardner, N. H., Gent, A. E., Gibbens, G. L. D., Goldberg, D. P. B., Grace, R. H., Graham, J. M., Gray, R. C. F., Green, M., Greenhalgh, R. M., Gregory, I. C., Griffiths, W. A. D., Lee, D. M. Gruebel, Hall, J. H., Hammond, K. C., Haas, P. A., Herzberg, L., Heughan, C., Hicks, E. P., Hilary-Jones, E. P., Hope, R. J., Inman, S. E., Jackson, R. K., Jenkins, Esmé S., Johnston, D. I., Jones, D. J., Joy, M. D., Kaye, H. H., Lloyd-Davies, R. W., Logan, R. L., Lord, Elizabeth J. A., Marks, C. J., Martin, E. C., Mathews, J. A., McCarthy, T. G., McLachlan, R., Melcher, D. H., Milward, T. M., Morgan, J. M., Moui, D. J., Negus, D., Newman, C. G. H., Nicholson, G. D., Norton, R., Nutting, M. G., Nicholls, J. T., Olver, R. E., Orr, N. W. M., Pratt, D. G., Prasad, D. S., Peachey, R. S., Petch, M. C., Phillips, D. J., Pim, H. P., Poole-Wilson, P. A., Prenton, M. A., Price, A. B., Pulvertaft, R. W., Rawlins, M. D., Redman, L. R., Reed, R. N., Rees, R., Rimmer, Diana M. D., Rippey, J. J., Rosenberg, M. T., Rosendorff, C., Rowland, R., Salisbury, Jennifer A., Sargent, N. W., Saunders, P. G., Shilling, J. S., Singh, A. K., Smith, M. E., Solan, M. J., Stephenson, R. H., Torrens, M., Trevelyan, H., Walker, G., Warden, N. J., Watts, J. I. M., Webb, D. A., White, J. E., Wight, D. G. D., Williams, Jean O., Willoughby, J. M. T., Wilson, D. S., and Alexander, B. L. more...

Published
1968

13. Publisher’s Note: Indications of Proton-Dominated Cosmic-Ray Composition above 1.6 EeV [Phys. Rev. Lett.104, 161101 (2010)]

Author

Abbasi, R. U., primary, Abu-Zayyad, T., additional, Al-Seady, M., additional, Allen, M., additional, Amman, J. F., additional, Anderson, R. J., additional, Archbold, G., additional, Belov, K., additional, Belz, J. W., additional, Bergman, D. R., additional, Blake, S. A., additional, Brusova, O. A., additional, Burt, G. W., additional, Cannon, C., additional, Cao, Z., additional, Deng, W., additional, Fedorova, Y., additional, Finley, C. B., additional, Gray, R. C., additional, Hanlon, W. F., additional, Hoffman, C. M., additional, Holzscheiter, M. H., additional, Hughes, G., additional, Hüntemeyer, P., additional, Ivanov, D., additional, Jones, B. F., additional, Jui, C. C. H., additional, Kim, K., additional, Kirn, M. A., additional, Loh, E. C., additional, Liu, J., additional, Lundquist, J. P., additional, Maestas, M. M., additional, Manago, N., additional, Marek, L. J., additional, Martens, K., additional, Matthews, J. A. J., additional, Matthews, J. N., additional, Moore, S. A., additional, O’Neill, A., additional, Painter, C. A., additional, Perera, L., additional, Reil, K., additional, Riehle, R., additional, Roberts, M., additional, Rodriguez, D., additional, Sasaki, N., additional, Schnetzer, S. R., additional, Scott, L. M., additional, Sinnis, G., additional, Smith, J. D., additional, Sokolsky, P., additional, Song, C., additional, Springer, R. W., additional, Stokes, B. T., additional, Stratton, S., additional, Thomas, S. B., additional, Thomas, J. R., additional, Thomson, G. B., additional, Tupa, D., additional, Zech, A., additional, and Zhang, X., additional more...

Published
2010
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14. Indications of Proton-Dominated Cosmic-Ray Composition above 1.6 EeV

Author

Abbasi, R. U., primary, Abu-Zayyad, T., additional, Al-Seady, M., additional, Allen, M., additional, Amman, J. F., additional, Anderson, R. J., additional, Archbold, G., additional, Belov, K., additional, Belz, J. W., additional, Bergman, D. R., additional, Blake, S. A., additional, Brusova, O. A., additional, Burt, G. W., additional, Cannon, C., additional, Cao, Z., additional, Deng, W., additional, Fedorova, Y., additional, Finley, C. B., additional, Gray, R. C., additional, Hanlon, W. F., additional, Hoffman, C. M., additional, Holzscheiter, M. H., additional, Hughes, G., additional, Hüntemeyer, P., additional, Ivanov, D., additional, Jones, B. F., additional, Jui, C. C. H., additional, Kim, K., additional, Kirn, M. A., additional, Loh, E. C., additional, Liu, J., additional, Lundquist, J. P., additional, Maestas, M. M., additional, Manago, N., additional, Marek, L. J., additional, Martens, K., additional, Matthews, J. A. J., additional, Matthews, J. N., additional, Moore, S. A., additional, O’Neill, A., additional, Painter, C. A., additional, Perera, L., additional, Reil, K., additional, Riehle, R., additional, Roberts, M., additional, Rodriguez, D., additional, Sasaki, N., additional, Schnetzer, S. R., additional, Scott, L. M., additional, Sinnis, G., additional, Smith, J. D., additional, Sokolsky, P., additional, Song, C., additional, Springer, R. W., additional, Stokes, B. T., additional, Stratton, S., additional, Thomas, S. B., additional, Thomas, J. R., additional, Thomson, G. B., additional, Tupa, D., additional, Zech, A., additional, and Zhang, X., additional more...

Published
2010
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20. An Upper Limit on the Electron‐Neutrino Flux from the HiRes Detector

Author

Abbasi, R. U., primary, Abu‐Zayyad, T., additional, Allen, M., additional, Amann, J. F., additional, Archbold, G., additional, Belov, K., additional, Belz, J. W., additional, Zvi, S. Y. Ben, additional, Bergman, D. R., additional, Biesiadecka, A., additional, Blake, S. A., additional, Boyer, J. H., additional, Brusova, O. A., additional, Burt, G. W., additional, Cannon, C., additional, Cao, Z., additional, Deng, W., additional, Fedorova, Y., additional, Findlay, J., additional, Finley, C. B., additional, Gray, R. C., additional, Hanlon, W. F., additional, Hoffman, C. M., additional, Holzscheiter, M. H., additional, Hughes, G., additional, Hüntemeyer, P., additional, Ivanov, D., additional, Jones, B. F, additional, Jui, C. C. H., additional, Kim, K., additional, Kirn, M. A., additional, Knapp, B. C., additional, Loh, E. C., additional, Maestas, M. M., additional, Manago, N., additional, Mannel, E. J., additional, Marek, L. J., additional, Martens, K., additional, Matthews, J. A. J., additional, Matthews, J. N., additional, Moore, S. A., additional, O’Neill, A., additional, Painter, C. A., additional, Perera, L., additional, Reil, K., additional, Riehle, R., additional, Roberts, M. D., additional, Rodriguez, D., additional, Sasaki, M., additional, Schnetzer, S. R., additional, Scott, L. M., additional, Seman, M., additional, Sinnis, G., additional, Smith, J. D., additional, Snow, R., additional, Sokolsky, P., additional, Song, C., additional, Springer, R. W., additional, Stokes, B. T., additional, Stratton, S. R., additional, Thomas, J. R., additional, Thomas, S. B., additional, Thomson, G. B., additional, Tupa, D., additional, Wiencke, L. R., additional, Zech, A., additional, and Zhang, X., additional more...

Published
2008
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21. First Observation of the Greisen-Zatsepin-Kuzmin Suppression

Author

Abbasi, R. U., primary, Abu-Zayyad, T., additional, Allen, M., additional, Amman, J. F., additional, Archbold, G., additional, Belov, K., additional, Belz, J. W., additional, Ben Zvi, S. Y., additional, Bergman, D. R., additional, Blake, S. A., additional, Brusova, O. A., additional, Burt, G. W., additional, Cannon, C., additional, Cao, Z., additional, Connolly, B. C., additional, Deng, W., additional, Fedorova, Y., additional, Finley, C. B., additional, Gray, R. C., additional, Hanlon, W. F., additional, Hoffman, C. M., additional, Holzscheiter, M. H., additional, Hughes, G., additional, Hüntemeyer, P., additional, Jones, B. F, additional, Jui, C. C. H., additional, Kim, K., additional, Kirn, M. A., additional, Loh, E. C., additional, Maestas, M. M., additional, Manago, N., additional, Marek, L. J., additional, Martens, K., additional, Matthews, J. A. J., additional, Matthews, J. N., additional, Moore, S. A., additional, O’Neill, A., additional, Painter, C. A., additional, Perera, L., additional, Reil, K., additional, Riehle, R., additional, Roberts, M., additional, Rodriguez, D., additional, Sasaki, N., additional, Schnetzer, S. R., additional, Scott, L. M., additional, Sinnis, G., additional, Smith, J. D., additional, Sokolsky, P., additional, Song, C., additional, Springer, R. W., additional, Stokes, B. T., additional, Thomas, S. B., additional, Thomas, J. R., additional, Thomson, G. B., additional, Tupa, D., additional, Westerhoff, S., additional, Wiencke, L. R., additional, Zhang, X., additional, and Zech, A., additional more...

Published
2008
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22. The principles of motivation and how to apply them

Author

Bucher, G. C and Gray, R. C

Subjects
General
Abstract

Motivation principles in industry based on Maslov theory of hierarchy of needs, discussing selection of supervisory personnel

Published
1971

23. Measurement of the Flux of Ultrahigh Energy Cosmic Rays from Monocular Observations by the High Resolution Fly’s Eye Experiment

Author

Abbasi, R. U., primary, Abu-Zayyad, T., additional, Amann, J. F., additional, Archbold, G., additional, Bellido, J. A., additional, Belov, K., additional, Belz, J. W., additional, Bergman, D. R., additional, Cao, Z., additional, Clay, R. W., additional, Cooper, M. D., additional, Dai, H., additional, Dawson, B. R., additional, Everett, A. A., additional, Fedorova, Yu. A., additional, Girard, J. H. V., additional, Gray, R. C., additional, Hanlon, W. F., additional, Hoffman, C. M., additional, Holzscheiter, M. H., additional, Hüntemeyer, P., additional, Jones, B. F, additional, Jui, C. C. H., additional, Kieda, D. B., additional, Kim, K., additional, Kirn, M. A., additional, Loh, E. C., additional, Manago, N., additional, Marek, L. J., additional, Martens, K., additional, Martin, G., additional, Matthews, J. A. J., additional, Matthews, J. N., additional, Meyer, J. R., additional, Moore, S. A., additional, Morrison, P., additional, Moosman, A. N., additional, Mumford, J. R., additional, Munro, M. W., additional, Painter, C. A., additional, Perera, L., additional, Reil, K., additional, Riehle, R., additional, Roberts, M., additional, Sarracino, J. S., additional, Sasaki, M., additional, Schnetzer, S. R., additional, Shen, P., additional, Simpson, K. M., additional, Sinnis, G., additional, Smith, J. D., additional, Sokolsky, P., additional, Song, C., additional, Springer, R. W., additional, Stokes, B. T., additional, Taylor, S. F., additional, Thomas, S. B., additional, Thompson, T. N., additional, Thomson, G. B., additional, Tupa, D., additional, Westerhoff, S., additional, Wiencke, L. R., additional, VanderVeen, T. D., additional, Zech, A., additional, and Zhang, X., additional more...

Published
2004
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26. Crevicular fluid prostaglandin E levels as a measure of the periodontal disease status of adult and juvenile periodontitis patients.

Author

Offenbacher, S., Odle, B. M., Gray, R. C., and Van Dyke, T. E.

Subjects
PERIODONTAL disease, GINGIVAL fluid, PROSTAGLANDINS, TISSUES, TOOTH loss, INFLAMMATION
Abstract

The measurement of crevicular fluid PGF (CF-PGE) as an indicator of periodontal disease status was investigated. The association between CF-PGE levels and the PGE content of the adjacent periodontal tissues was found to be highly significant (P = 5.3 × 10). The high correlation (r = 0.925) between the log CF-PGE level and the tissue PGE concentration indicates that CF levels can be used to reliably predict tissue levels. The CF-PGE measurements at each periodontal site were found to be highly reproducible. Samples from adult and juvenile periodontitis patients demonstrated that the mean CF-PGE levels were correlated with disease severity, as determined by mean attachment loss. The mean CF-PGE level in juvenile periodontitis patients was almost three-fold higher than that present in adult periodontitis (144.0 ± 28.0 ng/ml vs 57.5± 8.7 ng/ml, mean±S.E., significant at P = 0.002). The use of CF-PGE concentrations as an indicator of disease activity (i.e. longitudinal attachment loss) cannot be demonstrated by this cross-sectional study. However, the CF-PGE measurement has been demonstrated to be a non-invasive, sensitive, reproducible, and reliable reflection of tissue levels of PGE2. The association of increasing levels of CF-PGE with increased severity and aggressiveness of disease is consistent with PGE as an inflammatory mediator of tissue destruction. [ABSTRACT FROM AUTHOR] more...

Published
1984
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30. Lorazepam as a sedative-amnesic in an intensive Care unit

Author

Dundee, J. W., Johnston, Hilary M. L., and Gray, R. C.

Abstract

SummaryA clinical study was carried out to evaluate the usefulness of intravenous lorazepam, given for sedation instead of opiate narcotics or diazepam, in 25 seriously-ill patients being treated in a respiratory and intensive care unit. AH but 3 patients were on assisted ventilation. Standard doses of 4 mg lorazepam were given at 4 or 6-hourly intervals for periods up to 25 days. ECG, haemodynamic stability and biological determinations were monitored constantly. Apart from some delay in onset of action, lorazepam proved to be a useful sedative with diminished recall on the part of the patients. No side-effects were reported, nor was there any local reaction to the injection. Cardiac output was measured in 9 patients following intravenous administration of a single-dose of either 4 mg or 8 mg lorazepam. No significant changes were recorded. more...

Published
1976
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31. Population time budget for the yellow-bellied marmot

Author

Armitage, K. B., Salsbury, C. M., Barthelmess, E. L., Gray, R. C., and Kovach, A.

Abstract

Time budgets for 17 behaviors were analyzed for cohort, day-period, season- period and interactions among the main effects for three colonies of yellowbellied marmots in the Upper East River Valley in western Colorado. These effects explained up to 79% of the variation in the behaviors. Marmots allocated more time (40-60%, 110-265 min daily) above-ground to sitting/lying than to any other activity. Foraging was the other major activity (12-23%, 37 to 94 min daily). Vigilance/alert varied from 1.1 to 14.5% and from 12.0 to 71.7 min daily. Social status affected the time budget, especially time allocated to vigilance/alert. All other behaviors averaged about 5% or less except for out-of-sight and enterburrow. The adult male cohort spent significantly more time above-ground than all other cohorts and reproductive females allocated significantly more time to foraging than the other cohorts. The amount of time spent above-ground decreased linearly from the down-river site to the up-river site. The proportion of time spent above-ground was significantly less at mid day than in the morning or afternoon. Above-ground activity was lowest during gestation, increased during lactation, remained high during early post-lactation, and declined during the final season-period. The following significant relationships common to the three colonies suggest species characteristics or common environmental influences: more time allocated to foraging and foraging-vigilance in the afternoon and more time allocated to foraging-alert, alert, and locomotion during gestation and lactation than during post-lactation. Marmots adjust their behaviors according to prevailing conditions. The remaining significant relationships can be attributed to specific age-sex cohorts or to habitat differences. Because marmots allocate so much time to sitting/lying, we suggest that energy budgets are not constrained by foraging time but by time required to process ingested food. Similarly, time spent vigilant/alert does not seem to constrain energy intake. Social behavior is not limited by time, but could easily be expanded by spending less time inactive. In general, there do not seem to be tradeoffs among activities. Among other species of ground-dwelling sciurids, social behavior occupies a small proportion of the time budget, but the amount of time allocated to foraging and sitting/lying varies widely. more...

Published
1996
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32. Results of Five Generations of Selection for Low Backfat Thickness in Swine

Author

Gray, R. C., Tribble, L. F., Day, B. N., and Lasley, J. F.

Abstract

The effectiveness of selection for one trait, low backfat thickness, was investigated in Poland China pigs. Backfat probe measurements were made at a mean weight of 79.2 ± 2.5 kg. Measurements were made at three sites, shoulder, loin and ham and the average of the three measurements was used for selection. Mass selection resulted in approximately a 20 percent decrease in the backfat thickness of pigs as measured by the probe technique in five generations of selection. Response to selection at the three probe sites was similar. Realized heritability for the average of the three backfat probes was 0.32±0.09, while the heritability estimate obtained from intrasire regression of mean of offspring on dam was 0.56±0.09. The genetic correlations between backfat probes at 3 sites ranged from 0.59±0.10 to 0.82±0.06, suggesting that many of the same genes affected backfat at the different sites. The results of this study showed that mass selection for low backfat thickness was an effective method for reduction of backfat thickness. more...

Published
1968
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35. The selection and use of essential medicines

Author

Buschiazzo, P. M., Helali, A., Laing, R., Laporte, J. -R, Ofori-Adjei, D., Ombaka, E. M. A., Reidenberg, M. M., Sri Suryawati, Wannmacher, L., Bhutta, T. I., Renaud-Théry, F., Ha, T. H., Young, M. W., Walker, G., Boxtel, C. J., Asamoa-Baah, A., Gray, R. C. F., Gupta, U., Hill, S., Hogerzeil, H. V., Li, Y., Mehta, D. K., Offerhaus, L., Pillay, A., Quick, J. D., Wiffen, P. J., and Ziganshina, L. E. more...