58,910 research outputs found
Parker M. Pratt Funeral Remarks
No full textA speech given by President Jay L. Nelson at the funeral for Parker M. Pratt, a former Auto Mechanics instructor at the Salt Lake Area Vocational School. Pratt continued his association with the College from 1949 until his retirement in 1972 (when the College was known as Utah Technical College). Attached are the funeral service program, a photograph of Parker Pratt, an Interoffice Memo (May 15, 1972) from Jay L. Nelson regarding Mr. Pratt\u27s selection as an Outstanding Teacher to be honored by the Salt Lake Kiwanis Club, and a letter from Jay L. Nelson to Mr. Pratt regarding his retirement from the College.https://libarchive.slcc.edu/jaynelsonpapers/1000/thumbnail.jp
Galaxy-cluster gas-density distributions of the representative XMM-Newton cluster structure survey (REXCESS)
No full textWe present a study of the structural and scaling properties of the gas distributions in the intracluster medium (ICM) of 31 nearby (z < 0.2) clusters observed with XMM-Newton, which together comprise the Representative XMM-Newton Cluster Structure Survey (REXCESS). In contrast to previous studies, this sample is unbiased with respect to X-ray surface brightness and cluster dynamical state, and it fully samples the cluster X-ray luminosity function. The clusters cover a temperature range of 2.0-8.5 keV and possess a variety of morphologies. The sampling strategy allows us to compare clusters with a wide range of central cooling times on an equal footing. We applied a recently developed technique for the deprojection and PSF-deconvolution of X-ray surface brightness profiles to obtain non-parametric gas-density profiles out to distances ranging between 0.8 R500 and 1.5 R500. We scaled the gas density distributions to allow for the systems' differing masses and redshifts. The central gas densities differ greatly from system to system, with no clear correlation with system temperature. At intermediate radii (~ 0.3 R500), the scaled density profiles show much less scatter, with a clear dependence on system temperature. We find that the density at this radius scales proportionally to the square root of temperature, consistent with the presence of an entropy excess as suggested in previous literature. However, at larger scaled radii this dependence becomes weaker: clusters with kT > 3 keV scale self-similarly, with no temperature dependence of gas-density normalisation. The REXCESS sample allows us to investigate the correlations between cluster properties and dynamical state. We find no evidence of correlations between cluster dynamical state and either the gas density slope in the inner regions or temperature, but do find some evidence of a correlation between dynamical state and outer gas density slope. We also find a weak correlation between dynamical state and both central gas normalisation and inner cooling times, but this is only significant at the 10% level. We conclude that, for the X-ray cluster population as a whole, both the central gas properties and the angle-averaged, large-scale gas properties are linked to the cluster dynamical state. We also investigate the central cooling times of the clusters. While the cooling times span a wide range, we find no evidence of a significant bimodality in the distributions of central density, density gradient, or cooling time. Finally, we present the gas mass-temperature relation for the REXCESS sample, finding that , which is consistent with the expectation of self-similar scaling modified by the presence of an entropy excess in the inner regions of the cluster and consistent with earlier work on relaxed cluster samples. We measure a logarithmic intrinsic scatter in this relation of ~, which should be a good measure of the intrinsic scatter in the -T relation for the cluster population as a whole
The Citizens Bank of Jacksonville, From Eartha M. M. White to L.L. Pratt
No full textDocument: Cancelled check - The Citizens Bank of Jacksonville. Pay to L. L. Pratt one dollar. Counter check signed by Eartha M. M. White. Date: September 8, 191
The Citizens Bank of Jacksonville, From Eartha M. M. White to L. L. Pratt
No full textDocument: Cancelled check - The Citizens Bank of Jacksonville. Pay to the order of L. L. Pratt twenty-five dollars. Date: August 23, 193
The Citizens Bank of Jacksonville, From Eartha M. M. White to L. L. Pratt
No full textDocument: Cancelled check - The Citizens Bank of Jacksonville. Pay to L.L. Pratt fifteen dollars. Counter check signed by Eartha M. M. White. Date: September 23, 191
The Citizens Bank of Jacksonville, From Eartha M. M. White to Lawton L. Pratt, Inc.
No full textDocument: Cancelled check - The Citizens Bank of Jacksonville. Pay to the order of Lawton L. Pratt, Inc., one hundred ten dollars. Typed note on front: In full for funeral of Richard Lee. Date: June 10, 192
The universal galaxy cluster pressure profile from a representative sample of nearby systems (REXCESS) and the Y_SZ - M_500 relation
No full textWe investigate the regularity of cluster pressure profiles with REXCESS, a representative sample of 33 local (z < 0.2) clusters drawn from the REFLEX catalogue and observed with XMM-Newton. The sample spans a mass range of 1014 < M500 < 1015 , where M500 is the mass corresponding to a density contrast of 500. We derive an average profile from observations scaled by mass and redshift according to the standard self-similar model, and find that the dispersion about the mean is remarkably low, at less than 30 per cent beyond 0.2 R500, but increases towards the center. Deviations about the mean are related to both the mass and the thermo-dynamical state of the cluster. Morphologically disturbed systems have systematically shallower profiles while cooling core systems are more concentrated. The scaled profiles exhibit a residual mass dependence with a slope of ~0.12, consistent with that expected from the empirically-derived slope of the M500 – YX relation; however, the departure from standard scaling decreases with radius and is consistent with zero at R500. The scatter in the core and departure from self-similar mass scaling is smaller compared to that of the entropy profiles, showing that the pressure is the quantity least affected by dynamical history and non-gravitational physics. Comparison with scaled data from several state of the art numerical simulations shows good agreement outside the core. Combining the observational data in the radial range [0.03–1] R500 with simulation data in the radial range [1–4] R500, we derive a robust measure of the universal pressure profile, that, in an analytical form, defines the physical pressure profile of clusters as a function of mass and redshift up to the cluster “boundary”. Using this profile and direct spherical integration of the observed pressure profiles, we estimate the integrated Compton parameter Y and investigate its scaling with M500 and LX, the soft band X-ray luminosity. We consider both the spherically integrated quantity, Ysph(R), proportional to the gas thermal energy, and the cylindrically integrated quantity, Ycyl(R)=YSZ DA2, which is directly related to the Sunyaev-Zel'dovich (SZ) effect signal. From the low scatter of the observed Ysph(R500) – YX relation we show that variations in pressure profile shape do not introduce extra scatter into the Ysph(R500) – M500 relation as compared to that from the YX – M500 relation. The Ysph(R500) – M500 and Ysph(R500) – LX relations derived from the data are in excellent agreement with those expected from the universal profile. This profile is used to derive the expected YSZ – M500 and YSZ – LX relations for any aperture
Testing the physical oceanographic implications of the suggested sudden Black Sea infill 8400 years ago
No full textWe apply a shock-capturing numerical model based on the single-layer shallow water equations to an idealized geometry of the Black Sea and the Sea of Marmara in order to test the implications of a suggested sudden Black Sea infill 8400 years ago. The model resolves the two-dimensional flow upstream and downstream of the hydraulic jump provoked by the cascade of water from the Sea of Marmara into the Black Sea, which would occur during a sudden Black Sea infill. The modeled flow downstream of the hydraulic jump in the Black Sea would consist of a jet that is in part constrained by bathymetric contours. Guided by the Bosporus Canyon, the modeled jet reaches depths of up to 2000 m and could explain the origin of the sediment waves observed at this depth. At a late stage of the infill the modeled jet is attached to the coast and might account for the course of a submerged channel at the mouth of the Bosporus. The preservation of continuous barrier-washover-lagoonal fill systems occurring on the Black Sea shelf is, however, not easily reconcilable with the large flows over the southwest Black Sea shelf predicted by the model. Intensified flow in the upstream basin (Sea of Marmara) is restricted to the immediate vicinity of the Bosporus, suggesting that a sudden reconnection need not have disturbed sediments in the wider Sea of Marmara
Marriage record of Dishong, L. M. and Hague, Amanda
No full textMarriage license for L. M. Dishong and Amanda Hague. Edward E. Pratt was the Notary Public
Improving the Risk Concept: A Revision of Arrow-Pratt Theory in the Context of Controlled Dynamic Stochastic Environments
No full textIn the literature on risk, one generally assume that uncertainty is uniformly distributed over the entire working horizon, when the absolute risk-aversion index is negative and constant. From this perspective, the risk is totally exogenous, and thus independent of endogenous risks. The traditional measures of risk-aversion are generally too weak for making comparisons between risky situations. This can be highlighted in concrete problems in finance and insurance, context for which the Arrow-Pratt measures of risk-aversion give ambiguous results (Ross 1981). We improve the Arrow-Pratt approach (1964, 1971a, 1971b), which takes into account only attitudes towards small exogenous risks, by integrating in the analysis potentially high endogenous risks that are under the control of the agent. Based on multiple theoretical and empirical arguments, this new approach offers an elegant study of the close relationship between behavior, attitude and perceived risk.Endogenous risk-aversion, adaptive risk management, optimal risk-aversion threshold, excessive risk-averse behavior, risk perception, changing risk behavior.
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