117 results on '"GEORGE, E. M."'
Search Results
2. PyTAG: Challenges and Opportunities for Reinforcement Learning in Tabletop Games.
- Author
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Martin Balla, George E. M. Long, Dominik Jeurissen, James Goodman 0004, Raluca D. Gaina, and Diego Perez Liebana
- Published
- 2023
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- View/download PDF
3. A Study of Al–Mn Transition Edge Sensor Engineering for Stability
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George, E. M., Austermann, J. E., Beall, J. A., Becker, D., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crites, A. T., Dobbs, M. A., Everett, W., Halverson, N. W., Henning, J. W., Hilton, G. C., Holzapfel, W. L., Hubmayr, J., Irwin, K. D., Li, D., Lueker, M., McMahon, J. J., Mehl, J., Montgomery, J., Natoli, T., Nibarger, J. P., Niemack, M. D., Novosad, V., Ruhl, J. E., Sayre, J. T., Shirokoff, E., Story, K. T., Wang, G., Yefremenko, V., Yoon, K. W., and Young, E.
- Published
- 2014
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4. Measurement and validation of frailty as a predictor of outcomes in women undergoing major gynaecological surgery
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George, E M, Burke, W M, Hou, J Y, Tergas, A I, Chen, L, Neugut, A I, Ananth, C V, Hershman, D L, and Wright, J D
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- 2016
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5. An All Silicon Feedhorn-Coupled Focal Plane for Cosmic Microwave Background Polarimetry
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Hubmayr, J., Appel, J. W., Austermann, J. E., Beall, J. A., Becker, D., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crites, A. T., Essinger-Hileman, T., Fox, A., George, E. M., Halverson, N. W., Harrington, N. L., Henning, J. W., Hilton, G. C., Holzapfel, W. L., Irwin, K. D., Lee, A. T., Li, D., McMahon, J., Mehl, J., Natoli, T., Niemack, M. D., Newburgh, L. B., Nibarger, J. P., Parker, L. P., Schmitt, B. L., Staggs, S. T., Van Lanen, J., Wollack, E. J., and Yoon, K. W.
- Published
- 2012
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6. Shocks in the stacked Sunyaev-Zel'dovich profiles of clusters II: Measurements from SPT-SZ + Planck Compton-y map.
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(தயா), D Anbajagane, Chang, C, Jain, B, Adhikari, S, Baxter, E J, Benson, B A, Bleem, L E, Bocquet, S, Calzadilla, M S, Carlstrom, J E, Chang, C L, Chown, R, Crawford, T M, Crites, A T, Cui, W, de Haan, T, Mascolo, L Di, Dobbs, M A, Everett, W B, and George, E M
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GALAXY clusters ,LARGE scale structure (Astronomy) ,CLUSTER sampling ,POLARISCOPE ,REDSHIFT ,PHYSICAL cosmology ,GALACTIC redshift - Abstract
We search for the signature of cosmological shocks in stacked gas pressure profiles of galaxy clusters using data from the South Pole Telescope (SPT). Specifically, we stack the latest Compton- y maps from the 2500 deg
2 SPT-SZ survey on the locations of clusters identified in that same data set. The sample contains 516 clusters with mean mass |$\langle M_{\rm 200m}\rangle = 10^{14.9} \, {\rm M}_\odot$| and redshift 〈 z 〉 = 0.55. We analyse in parallel a set of zoom-in hydrodynamical simulations from the three hundred project. The SPT-SZ data show two features: (i) a pressure deficit at R / R200m = 1.08 ± 0.09, measured at 3.1σ significance and not observed in the simulations, and; (ii) a sharp decrease in pressure at R / R200m = 4.58 ± 1.24 at 2.0σ significance. The pressure deficit is qualitatively consistent with a shock-induced thermal non-equilibrium between electrons and ions, and the second feature is consistent with accretion shocks seen in previous studies. We split the cluster sample by redshift and mass, and find both features exist in all cases. There are also no significant differences in features along and across the cluster major axis, whose orientation roughly points towards filamentary structure. As a consistency test, we also analyse clusters from the Planck and Atacama Cosmology Telescope Polarimeter surveys and find quantitatively similar features in the pressure profiles. Finally, we compare the accretion shock radius (|$R_{\rm sh,\, acc}$|) with existing measurements of the splashback radius (Rsp ) for SPT-SZ and constrain the lower limit of the ratio, |$R_{\rm sh,\, acc}/R_{\rm sp}\gt 2.16 \pm 0.59$|. [ABSTRACT FROM AUTHOR]- Published
- 2022
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7. Combining Planck and SPT Cluster Catalogs: Cosmological Analysis and Impact on the Planck Scaling Relation Calibration.
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Salvati, L., Saro, A., Bocquet, S., Costanzi, M., Ansarinejad, B., Benson, B. A., Bleem, L. E., Calzadilla, M. S., Carlstrom, J. E., Chang, C. L., Chown, R., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W. B., Floyd, B., Grandis, S., George, E. M., Halverson, N. W., and Holder, G. P.
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PLANCK scale ,COSMIC background radiation ,LARGE scale structure (Astronomy) ,CATALOGS ,CALIBRATION ,CATALOGING - Abstract
We provide the first combined cosmological analysis of the South Pole Telescope (SPT) and Planck cluster catalogs. The aim is to provide an independent calibration for Planck scaling relations, exploiting the cosmological constraining power of the SPT-SZ cluster catalog and its dedicated weak lensing (WL) and X-ray follow-up observations. We build a new version of the Planck cluster likelihood. In the ν Λ CDM scenario, focusing on the mass slope and mass bias of Planck scaling relations, we find α SZ = 1.49 â' 0.10 + 0.07 and 1 â' b SZ = 0.69 â' 0.14 + 0.07 , respectively. The results for the mass slope show a âĽ4 Ď departure from the self-similar evolution, α
SZ ⼠1.8. This shift is mainly driven by the matter density value preferred by SPT data, Ωm = 0.30 ± 0.03, lower than the one obtained by Planck data alone, Ω m = 0.37 â' 0.06 + 0.02 . The mass bias constraints are consistent both with outcomes of hydrodynamical simulations and external WL calibrations, (1 â' b) ⼠0.8, and with results required by the Planck cosmic microwave background cosmology, (1 â' b) ⼠0.6. From this analysis, we obtain a new catalog of Planck cluster masses M500 . We estimate the ratio between the published Planck MSZ masses and our derived masses M500 , as a “measured mass bias,” 1 â' b M . We analyze the mass, redshift, and detection noise dependence of 1 â' b M , finding an increasing trend toward high redshift and low mass. These results mimic the effect of departure from self-similarity in cluster evolution, showing different dependencies for the low-mass, high-mass, low- z, and high- z regimes. [ABSTRACT FROM AUTHOR]- Published
- 2022
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8. Pathophysiology of hypertension in pre-eclampsia: a lesson in integrative physiology
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Palei, A. C., Spradley, F. T., Warrington, J. P., George, E. M., and Granger, J. P.
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- 2013
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9. Dusty starburst galaxies in the early Universe as revealed by gravitational lensing
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Vieira, J. D., Marrone, D. P., Chapman, S. C., De Breuck, C., Hezaveh, Y. D., Wei, A., Aguirre, J. E., Aird, K. A., Aravena, M., Ashby, M. L. N., Bayliss, M., Benson, B. A., Biggs, A. D., Bleem, L. E., Bock, J. J., Bothwell, M., Bradford, C. M., Brodwin, M., Carlstrom, J. E., Chang, C. L., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Fomalont, E. B., Fassnacht, C. D., George, E. M., Gladders, M. D., Gonzalez, A. H., Greve, T. R., Gullberg, B., Halverson, N. W., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Hunter, T. R., Keisler, R., Lee, A. T., Leitch, E. M., Lueker, M., Luong-Van, D., Malkan, M., McIntyre, V., McMahon, J. J., Mehl, J., Menten, K. M., Meyer, S. S., Mocanu, L. M., Murphy, E. J., Natoli, T., Padin, S., Plagge, T., Reichardt, C. L., Rest, A., Ruel, J., Ruhl, J. E., Sharon, K., Schaffer, K. K., Shaw, L., Shirokoff, E., Spilker, J. S., Stalder, B., Staniszewski, Z., Stark, A. A., Story, K., Vanderlinde, K., Welikala, N., and Williamson, R.
- Published
- 2013
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10. A massive, cooling-flow-induced starburst in the core of a luminous cluster of galaxies
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McDonald, M., Bayliss, M., Benson, B. A., Foley, R. J., Ruel, J., Sullivan, P., Veilleux, S., Aird, K. A., Ashby, M. L. N., Bautz, M., Bazin, G., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Egami, E., Forman, W. R., Garmire, G. P., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Harrington, N. L., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McMahon, J. J., Mehl, J., Meyer, S. S., Miller, E. D., Mocanu, L., Mohr, J. J., Montroy, T. E., Murray, S. S., Natoli, T., Padin, S., Plagge, T., Pryke, C., Rawle, T. D., Reichardt, C. L., Rest, A., Rex, M., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Shaw, L., Shirokoff, E., Simcoe, R., Song, J., Spieler, H. G., Stalder, B., Staniszewski, Z., Stark, A. A., Story, K., Stubbs, C. W., Šuhada, R., van Engelen, A., Vanderlinde, K., Vieira, J. D., Vikhlinin, A., Williamson, R., Zahn, O., and Zenteno, A.
- Published
- 2012
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11. Testosterone, signal coloration, and signal color perception in male zebra finch contests.
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Green, P. A., George, E. M., Rosvall, K. A., Johnsen, S., and Nowicki, S.
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COLOR vision , *ZEBRA finch , *GONADOTROPIN releasing hormone , *CONTESTS , *TESTOSTERONE , *RED , *ANIMAL coloration - Abstract
Many animals use assessment signals to resolve contests over limited resources while minimizing the costs of those contests. The carotenoid‐based orange to red bills of male zebra finches (Taeniopygia guttata) are thought to function as assessment signals in male–male contests, but behavioral analyses relating contest behaviors and outcomes to bill coloration have yielded mixed results. We examined the relationship between bill color and contests while incorporating measurements of color perception and testosterone (T) production, for an integrative view of aggressive signal behavior, production, and perception. We assayed the T production capabilities of 12 males in response to a gonadotropin‐releasing hormone (GnRH) challenge. We then quantified the initiation, escalation, and outcome of over 400 contests in the group, and measured bill color using calibrated photography. Finally, because signal perception can influence signal function, we tested how males perceive variation in bill coloration, asking if males exhibit categorical perception of bill color, as has been shown recently in female zebra finches. The data suggest that males with greater T production capabilities than their rivals were more likely to initiate contests against those rivals, while males with redder bills than their rivals were more likely to win contests. Males exhibited categorical color perception, but individual variation in the effect of categorical perception on color discrimination abilities did not predict any aspects of contest behavior or outcomes. Our results are consistent with the hypotheses that T plays a role in zebra finch contests and that bill coloration functions as an aggressive signal. We suggest future approaches, based on animal contest theory, for how links among signals, perception, and assessment can be tested. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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12. Prediction of Spinal Epidural Metastases
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Kienstra, George E. M., Terwee, Caroline B., Dekker, Friedo W., Canta, Leo R., Borstlap, Aernout C. W., Tijssen, Cees C., Bosch, D. Andries, and Tijssen, Jan G. P.
- Published
- 2000
13. SOLVING INVERSE STOCHASTIC PROBLEMS FROM DISCRETE PARTICLE OBSERVATIONS USING THE FOKKER--PLANCK EQUATION AND PHYSICS-INFORMED NEURAL NETWORKS.
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XIAOLI CHEN, LIU YANG, JINQIAO DUAN, and KARNIADAKIS, GEORGE E. M.
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INVERSE problems ,PROBABILITY density function ,FOKKER-Planck equation ,EVOLUTION equations ,EQUATIONS - Abstract
The Fokker--Planck (FP) equation governing the evolution of the probability density function (PDF) is applicable to many disciplines, but it requires specification of the coefficients for each case, which can be functions of space-time and not just constants and hence require the development of a data-driven modeling approach. When the data available is directly on the PDF, there exist methods for inverse problems that can be employed to infer the coefficients and thus determine the FP equation and subsequently obtain its solution. Herein, we address a more realistic scenario, where only sparse data are given on the particles' positions at a few time instants, which are not sufficient to accurately construct directly the PDF even at those times from existing methods, e.g., kernel estimation algorithms. To this end, we develop a general framework based on physicsinformed neural networks (PINNs) that introduces a new loss function using the Kullback--Leibler divergence to connect the stochastic samples with the FP equation to simultaneously learn the equation and infer the multidimensional PDF at all times. In particular, we consider two types of inverse problems, type I, where the FP equation is known but the initial PDF is unknown, and type II, in which, in addition to the unknown initial PDF, the drift and diffusion terms are also unknown. In both cases, we investigate problems with either Brownian or L\'evy noise or a combination of both. We demonstrate the new PINN framework in detail in the one-dimensional (1D) case, but we also provide results for up to five dimensions demonstrating that we can infer both the FP equation and dynamics simultaneously at all times with high accuracy using only very few discrete observations of the particles. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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14. Millimeter-wave Point Sources from the 2500 Square Degree SPT-SZ Survey: Catalog and Population Statistics.
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Everett, W. B., Zhang, L., Crawford, T. M., Vieira, J. D., Aravena, M., Archipley, M. A., Austermann, J. E., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Chapman, S., Crites, A. T., de Haan, T., Dobbs, M. A., George, E. M., Halverson, N. W., Harrington, N., Holder, G. P., and Holzapfel, W. L.
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DEMOGRAPHIC surveys ,POPULATION statistics ,ACTIVE galactic nuclei ,GALACTIC redshift ,GALAXY clusters - Abstract
We present a catalog of emissive point sources detected in the SPT-SZ survey, a contiguous 2530 square degree area surveyed with the South Pole Telescope (SPT) from 2008–2011 in three bands centered at 95, 150, and 220 GHz. The catalog contains 4845 sources measured at a significance of 4.5σ or greater in at least one band, corresponding to detections above approximately 9.8, 5.8, and 20.4 mJy in 95, 150, and 220 GHz, respectively. The spectral behavior in the SPT bands is used for source classification into two populations based on the underlying physical mechanisms of compact, emissive sources that are bright at millimeter wavelengths: synchrotron radiation from active galactic nuclei and thermal emission from dust. The latter population includes a component of high-redshift sources often referred to as submillimeter galaxies (SMGs). In the relatively bright flux ranges probed by the survey, these sources are expected to be magnified by strong gravitational lensing. The survey also contains sources consistent with protoclusters, groups of dusty galaxies at high redshift undergoing collapse. We cross-match the SPT-SZ catalog with external catalogs at radio, infrared, and X-ray wavelengths and identify available redshift information. The catalog splits into 3980 synchrotron-dominated and 865 dust-dominated sources, and we determine a list of 506 SMGs. Ten sources in the catalog are identified as stars. We calculate number counts for the full catalog, and synchrotron and dusty components, using a bootstrap method and compare our measured counts with models. This paper represents the third and final catalog of point sources in the SPT-SZ survey. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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15. Changes in the wetlands of hunting creek fairfax county, Virginia
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Newbury, George E. M.
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- 1981
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16. A RIESZ BASIS GALERKIN METHOD FOR THE TEMPERED FRACTIONAL LAPLACIAN.
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ZHIJIANG ZHANG, WEIHUA DENG, and KARNIADAKIS, GEORGE E. M.
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RIESZ spaces ,GALERKIN methods ,FRACTIONAL calculus ,LAPLACIAN matrices ,LEVY processes - Abstract
The fractional Laplacian &916;
&946;/2 is the generator of the &946;-stable Lévy process, which is the scaling limit of the Lévy flight. Due to the divergence of the second moment of the jump length of the Lévy flight, it may not be a suitable physical model in many practical applications. However, using a parameter &955; to exponentially temper the isotropic power law measure of the jump length leads to the tempered Lévy flight, which has finite second moment. For a short time the tempered Lévy flight exhibits the dynamics of Lévy flight, while after a sufficiently long time it turns to normal diffusion. The generator of the tempered &946;-stable Lévy process is the tempered fractional Laplacian (&916;+ &955;)&946;/2 [W. H. Deng et al., Multiscale Model. Simul., 16 (2018), pp. 125-149]. In the current work, we present new computational methods for the tempered fractional Laplacian equation, including the cases with the homogeneous and nonhomogeneous generalized Dirichlet type boundary conditions. We prove the well-posedness of the Galerkin weak formulation and provide convergence analysis of the single scaling B-spline and multiscale Riesz bases finite element methods. We propose a technique for efficiently generating the entries of the dense stiffness matrix and for solving the resulting algebraic equation by preconditioning. We also present several numerical experiments to verify the theoretical results. [ABSTRACT FROM AUTHOR]- Published
- 2018
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17. A COMPUTATIONAL STOCHASTIC METHODOLOGY FOR THE DESIGN OF RANDOM META-MATERIALS UNDER GEOMETRIC CONSTRAINTS.
- Author
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TSANTILI, IVI C., MIN HYUNG CHO, WEI CAI, and KARNIADAKIS, GEORGE E. M.
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STOCHASTIC analysis ,ELECTROMAGNETIC wave scattering - Abstract
We present a computational stochastic methodology for generating and optimizing random meta-material (MM) configurations with nonoverlapping geometric constraints subject to various types of covariances and distributions characterizing the randomness of the MM configura- tions. The methodology developed consists of three main components: (1) a deterministic solver for electromagnetic scattering from multiple objects, (2) the Karhunen-Loève (K-L) expansion to represent the correlated configurations of the scattering objects, and (3) the multi-element proba- bilistic collocation method (ME-PCM) to provide flexibility in achieving desired distributions of the MMs. In the current work, we employ random fields from a Spartan family that includes covariance functions with damped oscillatory behavior. The algorithm is applied to study light propagation through random layered heterojunctions and random 3-D MMs. We found that greater transmission and reflection, compared to the uniformly spaced structures, can be achieved for a structure with an oscillatory spacing profile along the propagation direction. Optimized configurations of the hetero- junctions and 3-D MMs have been found with larger or smaller transmission coefficients for different wave numbers of the incoming wave and different correlations. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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18. A SPECTRAL METHOD (OF EXPONENTIAL CONVERGENCE) FOR SINGULAR SOLUTIONS OF THE DIFFUSION EQUATION WITH GENERAL TWO-SIDED FRACTIONAL DERIVATIVE.
- Author
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ZHIPING MAO and KARNIADAKIS, GEORGE E. M.
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SINGULAR integrals , *STOCHASTIC convergence , *NUMERICAL solutions to partial differential equations , *FRACTIONAL calculus , *GALERKIN methods , *SOBOLEV spaces - Abstract
An open problem in the numerical solution of fractional partial differential equations (FPDEs) is how to obtain high-order accuracy for singular solutions; even for smooth right-hand sides solutions of FPDEs are singular. Here, we consider the one-dimensional diffusion equation with general two-sided fractional derivative characterized by a parameter p ∊ [0; 1]; for p = 1=2 we recover the Riesz fractional derivative, while for p = 1, 0 we obtain the one-sided fractional derivative. We employ a Petrov-Galerkin projection in a properly weighted Sobolev space with (two-sided) Jacobi polyfracnomials as basis and test functions. In particular, we derive these two-sided Jacobi polyfractonomials as eigenfunctions of a Sturm-Liouville problem with weights uniquely determined by the parameter p. We provide a rigorous analysis and obtain optimal error estimates that depend on the regularity of the forcing term, i.e., for smooth data (corresponding to singular solutions) we obtain exponential convergence, while for smooth solutions we obtain algebraic convergence. We demonstrate the sharpness of our error estimates with numerical examples, and we present comparisons with a competitive spectral collocation method of tunable accuracy. We also investigate numerically deviations from the theory for inhomogeneous Dirichlet boundary conditions as well as for a fractional diffusion-reaction equation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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19. NUMERICAL GAUSSIAN PROCESSES FOR TIME-DEPENDENT AND NONLINEAR PARTIAL DIFFERENTIAL EQUATIONS.
- Author
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Raissi, Maziar, Perdikaris, Paris, and Karniadakis, George E. M.
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PARTIAL differential equations ,GAUSSIAN processes - Abstract
We introduce the concept of numerical Gaussian processes, which we define as Gauss- ian processes with covariance functions resulting from temporal discretization of time-dependent partial differential equations. Numerical Gaussian processes, by construction, are designed to deal with cases where (a) all we observe are noisy data on black-box initial conditions, and (b) we are interested in quantifying the uncertainty associated with such noisy data in our solutions to time- dependent partial differential equations. Our method circumvents the need for spatial discretization of the differential operators by proper placement of Gaussian process priors. This is an attempt to construct structured and data-efficient learning machines, which are explicitly informed by the underlying physics that possibly generated the observed data. The effectiveness of the proposed approach is demonstrated through several benchmark problems involving linear and nonlinear time- dependent operators. In all examples, we are able to recover accurate approximations of the latent solutions, and consistently propagate uncertainty, even in cases involving very long time integration. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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- View/download PDF
20. Readiness Assessment Framework for Implementation of Mobile e-Healthcare in Rural South Africa.
- Author
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Ilorah, Appolonia I., Ditsa, George E. M., and Mokwena, Sello N.
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ELECTRONIC commerce , *HEALTH care industry , *PREPAREDNESS , *MEDICAL care , *MEDICAL quality control - Abstract
Although healthcare is the biggest service industry in the world, it has yet to realise the full potential of the e-business revolution in the form of e-Healthcare due to many complex challenges. E-Healthcare also does not solve all the problems of rural and remote communities with geographical barriers, because most of the rural and remote areas that e-Healthcare are supposed to help have no electricity connections and other infrastructure needed by e-Healthcare systems. Mobile e-Healthcare removes the restrictions imposed by infrastructure challenged, underserved population, rural geographical locations, wires and cables and enables patients to benefit from increased mobility provided by e-Healthcare. The main objective of this study was therefore to identify e-Healthcare readiness assessment factors in the literature and use them to develop a Mobile e-Healthcare readiness assessment framework for the implementation of Mobile e-Healthcare in rural South Africa health facilities. [ABSTRACT FROM AUTHOR]
- Published
- 2017
21. MULTIFIDELITY INFORMATION FUSION ALGORITHMS FOR HIGH-DIMENSIONAL SYSTEMS AND MASSIVE DATA SETS.
- Author
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PERDIKARIS, PARIS, VENTURI, DANIELE, and KARNIADAKIS, GEORGE E. M.
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FUSION (Phase transformation) ,GAUSSIAN processes ,MULTIVARIATE analysis ,ANALYSIS of variance ,DISTRIBUTION (Probability theory) ,MATHEMATICAL models - Abstract
We develop a framework for multifidelity information fusion and predictive inference in high-dimensional input spaces and in the presence of massive data sets. Hence, we tackle simultaneously the "big N" problem for big data and the curse of dimensionality in multivariate parametric problems. The proposed methodology establishes a new paradigm for constructing response surfaces of high-dimensional stochastic dynamical systems, simultaneously accounting for multifidelity in physical models as well as multifidelity in probability space. Scaling to high dimensions is achieved by data-driven dimensionality reduction techniques based on hierarchical functional decompositions and a graph-theoretic approach for encoding custom autocorrelation structure in Gaussian process priors. Multifidelity information fusion is facilitated through stochastic autoregressive schemes and frequency-domain machine learning algorithms that scale linearly with the data. Taking together these new developments leads to linear complexity algorithms as demonstrated in benchmark problems involving deterministic and stochastic fields in up to 10
5 input dimensions and 105 training points on a standard desktop computer. [ABSTRACT FROM AUTHOR]- Published
- 2016
- Full Text
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22. A GENERALIZED SPECTRAL COLLOCATION METHOD WITH TUNABLE ACCURACY FOR VARIABLE-ORDER FRACTIONAL DIFFERENTIAL EQUATIONS.
- Author
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FANHAI ZENG, ZHONGQIANG ZHANG, and KARNIADAKIS, GEORGE E. M.
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COLLOCATION methods ,FRACTIONAL differential equations ,JACOBI polynomials ,PARTIAL differential equations ,INTEGRALS ,NUMERICAL analysis - Abstract
We generalize existing Jacobi-Gauss-Lobatto collocation methods for variable-order fractional differential equations using a singular approximation basis in terms of weighted Jacobi polynomials of the form (1 ± x)μP
a,b j (x), where μ > -1. In order to derive the differentiation matrices of the variable-order fractional derivatives, we develop a three-term recurrence relation for both integrals and derivatives of these weighted Jacobi polynomials, hence extending the three-term recurrence relationship of Jacobi polynomials. The new spectral collocation method is applied to solve fractional ordinary and partial differential equations with endpoint singularities. We demonstrate that the singular basis enhances greatly the accuracy of the numerical solution by properly tuning the parameter μ, even for cases where we do not know explicitly the form of singularity in the solution at the boundaries. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
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23. TIME-SPLITTING SCHEMES FOR FRACTIONAL DIFFERENTIAL EQUATIONS I: SMOOTH SOLUTIONS.
- Author
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WANRONG CAO, ZHONGQIANG ZHANG, and KARNIADAKIS, GEORGE E. M.
- Subjects
FRACTIONAL differential equations ,SMOOTHNESS of functions ,STOCHASTIC convergence ,NONLINEAR equations ,FRACTIONAL calculus - Abstract
We propose three time-splitting schemes for nonlinear time-fractional differential equations with smooth solutions, where the order of the fractional derivative is 0 < α < 1. While one of the schemes is of order α, the other two schemes are of order 1 + α and 2 - α and thus they can be combined to provide flexible numerical methods with convergence order no less than 3/2. We prove the convergence and stability of the proposed schemes. Numerical examples illustrate the flexibility and the efficiency of these time-splitting schemes and show that they work for multirate and stiff time-fractional differential systems effectively. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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24. TEMPERED FRACTIONAL STURM-LIOUVILLE EIGENPROBLEMS.
- Author
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ZAYERNOURI, MOHSEN, AINSWORTH, MARK, and KARNIADAKIS, GEORGE E. M.
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NUMERICAL solutions to Sturm-Liouville equations ,RANDOM walks ,EIGENFUNCTIONS ,EIGENVALUES ,NUMERICAL solutions to boundary value problems - Abstract
Continuum-time random walk is a general model for particle kinetics, which allows for incorporating waiting times and/or non-Gaussian jump distributions with divergent second moments to account for Lévy flights. Exponentially tempering the probability distribution of the waiting times and the anomalously large displacements results in tempered-stable L´evy processes with finite moments, where the fluid (continuous) limit leads to the tempered fractional diffusion equation. The development of fast and accurate numerical schemes for such nonlocal problems requires a new spectral theory and suitable choice of basis functions. In this study, we introduce two classes of regular and singular tempered fractional Sturm-Liouville problems of two kinds (TFSLP-I and TFSLP-II) of order v ∈ (0, 2). In the regular case, the corresponding tempered differential operators are associated with tempering functions pI (x) = exp(2τ) and pII (x) = exp(-2τ), τ ≥ 0, respectively, in the regular TFSLP-I and TFSLP-II, which do not vanish in [-1, 1]. In contrast, the corresponding differential operators in the singular setting are associated with different forms of pI (x) = exp(2τ)(1-x)1+α(1+ x)1+β and pII (x) = exp(-2τ)(1 - x)1+α(1 + x)1+β, vanishing at x = ±1 in the singular TFSLP-I and TFSLP-II, respectively. The aforementioned tempered fractional differential operators are both of tempered Riemann--Liouville and tempered Caputo type of fractional order μ = v/2 ∈ (0, 1). We prove the well-posedness of the boundary-value problems and that the eigenvalues of the regular tempered problems are real-valued and the corresponding eigenfunctions are orthogonal. Next, we obtain the explicit eigensolutions to TFSLP-I and -II as nonpolynomial functions, which we define as tempered Jacobi poly-fractonomials. These eigenfunctions are orthogonal with respect to the weight function associated with TFSLP-I and -II. Finally, we introduce these eigenfunctions as new basis (and test) functions for spectrally accurate approximation of functions and tempered-fractional differential operators. To this end, we further develop a Petrov-Galerkin spectral method for solving tempered fractional ODEs, followed by the corresponding stability and convergence analysis, which validates the achieved spectral convergence in our simulations. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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25. Transformações recentes da indústria farmacêutica: um exame da experiência mundial e brasileira no século XXI.
- Author
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Kornis, George E. M., Braga, Maria Helena, and de Paula, Patrícia A. Baumgratz
- Abstract
This article discusses the characteristics and trends of the global and Brazilian pharmaceutical industry in the 21st century, its transformations and industry trends, and its actors. Qualitative research and the technique of document analysis allowed us to check that in early 20th century, the global pharmaceutical industry was characterized by homogeneous structure and reduced supply of products. After the Second World War, there was strengthening of the production of medicines based on chemical synthesis and diversification of supply and demand for drugs. The pharmaceutical market has shifted from broader competition for one of oligopolistic character. In the 1990s, these industries' portfolio expanded to areas of animal health, hygiene / personal care and nutrition / dietetics. In the 2000s, the global pharmaceutical industry intensified this process, and due to the expiration of patents on medicines, focused on the generic segment, acquiring companies in emerging markets. The Brazilian pharmaceutical industry followed the lines of the global pharmaceutical industry and started to invest in the production of generic medicines, herbal and advancement of biotechnology, with public financial support of the BNDES. This context continues to demand advances in health innovation, and demands of the health regulation to face the challenges arising from this great transformation. It is worth mentioning the challenges relating to costs of drugs and their strong impact on health systems, particularly those of more inclusive character. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
26. A MEASUREMENT OF THE SECONDARY-CMB AND MILLIMETER-WAVE-FOREGROUND BISPECTRUM USING 800 deg2 OF SOUTH POLE TELESCOPE DATA.
- Author
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Crawford, T. M., Schaffer, K. K., Bhattacharya, S., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H-M., Crites, A. T., Haan, T. de, Dobbs, M. A., Dudley, J., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., and Hrubes, J. D.
- Subjects
GALAXY spectra ,SPECTRUM analysis ,ACTIVE galactic nuclei ,COSMIC background radiation ,EXTRAGALACTIC distances - Abstract
We present a measurement of the angular bispectrum of the millimeter-wave sky in observing bands centered at roughly 95, 150, and 220 GHz, on angular scales of 1′ ≲ θ ≲ 10′ (multipole number 1000 ≲ l ≲ 10,000). At these frequencies and angular scales, the main contributions to the bispectrum are expected to be the thermal Sunyaev-Zel'dovich (tSZ) effect and emission from extragalactic sources, predominantly dusty, star-forming galaxies (DSFGs) and active galactic nuclei. We measure the bispectrum in 800 deg
2 of three-band South Pole Telescope data, and we use a multi-frequency fitting procedure to separate the bispectrum of the tSZ effect from the extragalactic source contribution. We simultaneously detect the bispectrum of the tSZ effect at >10σ, the unclustered component of the extragalactic source bispectrum at >5σ in each frequency band, and the bispectrum due to the clustering of DSFGs—i.e., the clustered cosmic infrared background (CIB) bispectrum—at >5σ. This is the first reported detection of the clustered CIB bispectrum. We use the measured tSZ bispectrum amplitude, compared to model predictions, to constrain the normalization of the matter power spectrum to be σ8 = 0.787 ± 0.031 and to predict the amplitude of the tSZ power spectrum at l = 3000. This prediction improves our ability to separate the thermal and kinematic contributions to the total SZ power spectrum. The addition of bispectrum data improves our constraint on the tSZ power spectrum amplitude by a factor of two compared to power spectrum measurements alone and demonstrates a preference for a nonzero kinematic SZ (kSZ) power spectrum, with a derived constraint on the kSZ amplitude at l = 3000 of AkSZ = 2.9 ± 1.6 μK2 , or AkSZ = 2.6 ± 1.8 μK2 if the default AkSZ > 0 prior is removed. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
27. CONSTRAINTS ON COSMOLOGY FROM THE COSMIC MICROWAVE BACKGROUND POWER SPECTRUM OF THE 2500 deg2 SPT-SZ SURVEY.
- Author
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Hou, Z., Reichardt, C. L., Story, K. T., Follin, B., Keisler, R., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crawford, T. M., Crites, A. T., Haan, T. de, Putter, R. de, Dobbs, M. A., Dodelson, S., Dudley, J., George, E. M., and Halverson, N. W.
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METAPHYSICAL cosmology ,ASTRONOMY ,COSMIC background radiation ,ASTROPHYSICAL radiation ,PHYSICAL cosmology - Abstract
We explore extensions to the ΛCDM cosmology using measurements of the cosmic microwave background (CMB) from the recent SPT-SZ survey, along with data from WMAP7 and measurements of H
0 and baryon acoustic oscillation (BAO). We check for consistency within ΛCDM between these data sets, and find some tension. The CMB alone gives weak support to physics beyond ΛCDM, due to a slight trend relative to ΛCDM of decreasing power toward smaller angular scales. While it may be due to statistical fluctuation, this trend could also be explained by several extensions. We consider running of the primordial spectral index (dns /dln k), as well as two extensions that modify the damping tail power (the primordial helium abundance Yp and the effective number of neutrino species Neff ) and one that modifies the large-scale power due to the integrated Sachs-Wolfe effect (the sum of neutrino masses ∑mν ). These extensions have similar observational consequences and are partially degenerate when considered simultaneously. Of the six one-parameter extensions considered, we find CMB to have the largest preference for dns /dln k with –0.046 < dns /dln k < –0.003 at 95% confidence, which strengthens to a 2.7σ indication of dns /dln k < 0 from CMB+BAO+H0 . Detectable dns /dln k ≠ 0 is difficult to explain in the context of single-field, slow-roll inflation models. We find Neff = 3.62 ± 0.48 for the CMB, which tightens to Neff = 3.71 ± 0.35 from CMB+BAO+H0 . Larger values of Neff relieve the mild tension between CMB, BAO, and H0 . When the Sunyaev-Zel'dovich selected galaxy cluster abundances () data are also included, we obtain Neff = 3.29 ± 0.31. Allowing for ∑mν gives a 3.0σ detection of ∑mν > 0 from CMB+BAO+H0 +. The median value is (0.32 ± 0.11) eV, a factor of six above the lower bound set by neutrino oscillation observations. All data sets except H0 show some preference for massive neutrinos; data combinations including H0 favor nonzero masses only if BAO data are also included. We also constrain the two-parameter extensions Neff + ∑mν and Neff + Yp to explore constraints on additional light species and big bang nucleosynthesis, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
28. TIME CORRELATION FUNCTIONS OF BROWNIAN MOTION AND EVALUATION OF FRICTION COEFFICIENT IN THE NEAR-BROWNIAN-LIMIT REGIME.
- Author
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CHANGHO KIM and KARNIADAKIS, GEORGE E. M.
- Subjects
- *
MOLECULAR dynamics , *WIENER processes , *MOMENTUM (Mechanics) , *FRICTION , *STATISTICAL correlation , *ASYMPTOTIC expansions - Abstract
The exponentially decaying behavior of the momentum-momentum and momentumforce time correlation functions of Brownian motion at large times has been extensively used for the numerical evaluation of the friction coefficient γ from molecular dynamics simulations. We perform numerical analysis on these methods and address issues related to the appropriate choice of large time and the rate of convergence of these methods. To this end, we obtain asymptotic expansions of the time correlation functions with respect to the reduced mass μ of the Brownian particle. For two important limit procedures of achieving the Brownian limit, certain forms of the asymptotic expansion of the Mori memory function K(t) are introduced by physical arguments, and then the asymptotic expansions of the time correlation functions are expressed in terms of the limit of K(t), i.e., K0(t) = limμ→∝ K(t), and the next-order correction term K1(t). For the infinite mass limit case, we show that the numerical methods of estimating γ from the exponential decay of the time correlation functions produce γ + O(μ-1), where the first-order correction depends on the microscopic nature of K0(t) (i.e., deviation of K0(t) from the Dirac delta function γδ(t)) as well as the contribution of K1(t) (i.e., deviation of K(t) from K0(t)). We also analyze the ratio of the momentum-force correlation function to the momentum-momentum correlation function, which gives instantaneous exponential decay rate. For the thermodynamic limit case, we consider the Rayleigh gas system to investigate the finite-volume effect due to the boundary conditions and to demonstrate that the lowest-order terms of the asymptotic expansions may fail to describe some characteristic behavior of the time correlation functions. We perform systematic molecular dynamics simulations of the Rayleigh gas system to confirm the theoretical predictions. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
29. COARSE-GRAINED MODELING OF PROTEIN UNFOLDING DYNAMICS.
- Author
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DENG, MINGGE and KARNIADAKIS, GEORGE E. M.
- Subjects
- *
DENATURATION of proteins , *PROTEIN-protein interactions , *COVALENT bonds , *ACTIVATION energy , *MOLECULAR dynamics , *MATHEMATICAL models - Abstract
We present a new dynamic elastic network model (DENM) that describes the unfolding process of a force-loaded protein. The protein interaction network and its potentials are constructed based on information of its native-state structure obtained from the Protein Data Bank, with network nodes positioned at the Cα coordinates of the protein backbone. Specifically, to mimic the unfolding process, i.e., to simulate the process of overcoming the local energy barrier on the free energy landscape with force loading, the noncovalent protein network bonds (i.e., hydrogen bonds, salt bridges, hydrophobic contacts, etc.) are broken one-by-one with a certain probability, while the strong covalent bonds along the backbone (i.e., peptide bonds, disulfide bonds, etc.) are kept intact. The jumping event from local energy minima (bonds breaking rate) are chosen according to Kramer's theory and the Bell model. Moreover, we exploit the self-similar structure of proteins at different scales to design an effective coarse-graining procedure for DENM with optimal parameter selection. The robustness of DENM is validated by coarse-grained molecular dynamics (MD) simulation against atomistic MD simulation of force-extension processes of the Fibrinogen and Titin Immunoglobulin proteins. We observe that the native structure of the proteins determines the total unfolding dynamics (including large deviations) and not just the fluctuations around the native state. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
30. A MEASUREMENT OF THE COSMIC MICROWAVE BACKGROUND DAMPING TAIL FROM THE 2500-SQUARE-DEGREE SPT-SZ SURVEY.
- Author
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Story, K. T., Reichardt, C. L., Hou, Z., Keisler, R., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crawford, T. M., Crites, A. T., Haan, T. de, Dobbs, M. A., Dudley, J., Follin, B., George, E. M., Halverson, N. W., Holder, G. P., and Holzapfel, W. L.
- Subjects
COSMIC background radiation ,METAPHYSICAL cosmology ,ANISOTROPY ,BARYON spectra ,GRAVITATIONAL lenses - Abstract
We present a measurement of the cosmic microwave background (CMB) temperature power spectrum using data from the recently completed South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. This measurement is made from observations of 2540 deg
2 of sky with arcminute resolution at 150 GHz, and improves upon previous measurements using the SPT by tripling the sky area. We report CMB temperature anisotropy power over the multipole range 650 < ℓ < 3000. We fit the SPT bandpowers, combined with the 7 yr Wilkinson Microwave Anisotropy Probe (WMAP7) data, with a six-parameter ΛCDM cosmological model and find that the two datasets are consistent and well fit by the model. Adding SPT measurements significantly improves ΛCDM parameter constraints; in particular, the constraint on θs tightens by a factor of 2.7. The impact of gravitational lensing is detected at 8.1σ, the most significant detection to date. This sensitivity of the SPT+WMAP7 data to lensing by large-scale structure at low redshifts allows us to constrain the mean curvature of the observable universe with CMB data alone to be . Using the SPT+WMAP7 data, we measure the spectral index of scalar fluctuations to be ns = 0.9623 ± 0.0097 in the ΛCDM model, a 3.9σ preference for a scale-dependent spectrum with ns < 1. The SPT measurement of the CMB damping tail helps break the degeneracy that exists between the tensor-to-scalar ratio r and ns in large-scale CMB measurements, leading to an upper limit of r < 0.18 (95% C.L.) in the ΛCDM+r model. Adding low-redshift measurements of the Hubble constant (H0 ) and the baryon acoustic oscillation (BAO) feature to the SPT+WMAP7 data leads to further improvements. The combination of SPT+WMAP7+H0 +BAO constrains ns = 0.9538 ± 0.0081 in the ΛCDM model, a 5.7σ detection of ns < 1, and places an upper limit of r < 0.11 (95% C.L.) in the ΛCDM+r model. These new constraints on ns and r have significant implications for our understanding of inflation, which we discuss in the context of selected single-field inflation models. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
31. EXTRAGALACTIC MILLIMETER-WAVE POINT-SOURCE CATALOG, NUMBER COUNTS AND STATISTICS FROM 771 deg2 OF THE SPT-SZ SURVEY.
- Author
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Mocanu, L. M., Crawford, T. M., Vieira, J. D., Aird, K. A., Aravena, M., Austermann, J. E., Benson, B. A., Béthermin, M., Bleem, L. E., Bothwell, M., Carlstrom, J. E., Chang, C. L., Chapman, S., Cho, H.-M., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W. B., George, E. M., and Halverson, N. W.
- Subjects
ACTIVE galactic nuclei ,EXTRAGALACTIC distances ,REDSHIFT ,SYNCHROTRON radiation ,GALAXIES - Abstract
We present a point-source catalog from 771 deg
2 of the South Pole Telescope Sunyaev-Zel'dovich survey at 95, 150, and 220 GHz. We detect 1545 sources above 4.5σ significance in at least one band. Based on their relative brightness between survey bands, we classify the sources into two populations, one dominated by synchrotron emission from active galactic nuclei, and one dominated by thermal emission from dust-enshrouded star-forming galaxies. We find 1238 synchrotron and 307 dusty sources. We cross-match all sources against external catalogs and find 189 unidentified synchrotron sources and 189 unidentified dusty sources. The dusty sources without counterparts are good candidates for high-redshift, strongly lensed submillimeter galaxies. We derive number counts for each population from 1 Jy down to roughly 11, 4, and 11 mJy at 95, 150, and 220 GHz. We compare these counts with galaxy population models and find that none of the models we consider for either population provide a good fit to the measured counts in all three bands. The disparities imply that these measurements will be an important input to the next generation of millimeter-wave extragalactic source population models. [ABSTRACT FROM AUTHOR]- Published
- 2013
- Full Text
- View/download PDF
32. A COSMIC MICROWAVE BACKGROUND LENSING MASS MAP AND ITS CORRELATION WITH THE COSMIC INFRARED BACKGROUND.
- Author
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HOLDER, G. P., VIERO, M. P., ZAHN, O., AIRD, K. A., BENSON, B. A., BHATTACHARYA, S., BLEEM, L. E., BOCK, J., BRODWIN, M., CARLSTROM, J. E., C. L. CHANG, H-M. CHO, CONLEY, A., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DOBBS, M. A., DUDLEY, J., GEORGE, E. M., and HALVERSON, N. W.
- Published
- 2013
- Full Text
- View/download PDF
33. THE FIRST PUBLIC RELEASE OF SOUTH POLE TELESCOPE DATA: MAPS OF A 95 deg² FIELD FROM 2008 OBSERVATIONS.
- Author
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Schaffer, K. K., Crawford, T. M., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crites, A. T., De Haan, T., Dobbs, M. A., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Joy, M., Keisler, R., and Knox, L.
- Subjects
ELECTRONIC data processing management ,GALAXY clusters ,LARGE astronomical telescopes ,EMISSIVITY - Abstract
The South Pole Telescope (SPT) has nearly completed a 2500 deg² survey of the southern sky in three frequency bands. Here, we present the first public release of SPT maps and associated data products. We present arcminute-resolution maps at 150 GHz and 220 GHz of an approximately 95 deg² field centered at R.A. 82°.17, decl.-55°. The field was observed to a depth of approximately 17 µK arcmin at 150 GHz and 41 µK arcmin at 220 GHz during the 2008 austral winter season. Two variations on map filtering and map projection are presented, one tailored for producing catalogs of galaxy clusters detected through their Sunyaev-Zel'dovich effect signature and one tailored for producing catalogs of emissive sources. We describe the data processing pipeline, and we present instrument response functions, filter transfer functions, and map noise properties. All data products described in this paper are available for download at http://pole.uchicago.edu/public/data/maps/ra5h30dec-55 and from the NASA Legacy Archive for Microwave Background Data Analysis server. This is the first step in the eventual release of data from the full 2500 deg² SPT survey. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
34. A MEASUREMENT OF THE DAMPING TAIL OF THE COSMIC MICROWAVE BACKGROUND POWER SPECTRUM WITH THE SOUTH POLE TELESCOPE.
- Author
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Keisler, R., Reichardt, C. L., Aird, K. A., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Crawford, T. M., Crites, A. T., De Haan, T., Dobbs, M. A., Dudley, J., George, E. M., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hou, Z., and Hrubes, J. D.
- Subjects
COSMIC background radiation ,NEUTRINOS ,HELIUM ,HUBBLE constant ,REDSHIFT ,GALAXY clusters - Abstract
We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) using data from the South Pole Telescope (SPT). The data consist of 790 deg² of sky observed at 150 GHz during 2008 and 2009. Here we present the power spectrum over the multipole range 650 < ℓ < 3000, where it is dominated by primary CMB anisotropy. We combine this power spectrum with the power spectra from the seven-year Wilkinson Microwave Anisotropy Probe (WMAP) data release to constrain cosmological models. We find that the SIM and WMAP data are consistent with each other and, when combined, are well fit by a spatially flat, ACDM cosmological model. The SVT+WMAP constraint on the spectral index of scalar fluctuations is n
s = 0.9663 ± 0.0112. We detect, at ~5σ significance, the effect of gravitational lensing on the CMB power spectrum, and find its amplitude to be consistent with the ACDM cosmological model. We explore a number of extensions beyond the ACDM model. Each extension is tested independently, although there are degeneracies between some of the extension parameters We constrain the tensor-to-scalar ratio to be r < 0.21 (95% CL) and constrain the running of the scalar spectral index to be dns /d lnk = -0.024 ± 0.013. We strongly detect the effects of primordial helium and neutrinos on the CMB; a model without helium is rejected at 7.7σ, while a model without neutrinos is rejected at 7.5σ. The primordial helium abundance is measured to be Yp = 0.296 ± 0.030, and the effective number of relativistic. species is measured to be Neff = 3.85 ± 0.62. The constraints on these models are strengthened when the CMB data are combined with measurements of the Hubble constant and the baryon acoustic oscillation feature. Notable improvements include ns = 0.9668 ± 0.0093, r < 0.17 (95% CL), and Neff = 3.86 ± 0.42. The SPT+WMAP data show a mild preference for low power in the CMB damping tail, and while this preference may be accommodated by models that have a negative spectral running, a high primordial helium abundance, or a high effective number of relativistic species, such models are disfavored by the abundance of low-redshift galaxy clusters. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
35. A regulação em saúde no Brasil: um breve exame das décadas de 1999 a 2008.
- Author
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Kornis, George E. M., Braga, Maria Helena, Fagundes, Marise, and de Paula, Patrícia A. Baumgratz
- Subjects
- *
HEALTH policy , *HEALTH , *HEALTH care industry , *PERSONAL care products industry , *GOVERNMENT policy - Abstract
This paper discusses the Brazilian experience of health regulation from 1999 to 2008. It aims to understand the interfaces of the regulatory process in health in Brazil, particularly the pharmaceutical industry, seeking to identify, historically, the actors and contexts relating to the proceedings. The research was based on literature review and survey of the resolutions of the Board of the National Health Surveillance Agency. This survey identified the concentration of these resolutions in the following areas: drugs, human resources and food. Regarding drugs, emphasis was placed in three key words: drug registration, practices and substances subject to special control. In addition to a brief history of the evolution of Brazilian health surveillance, this paper focused on the regulatory aspects of the National Health Surveillance Agency and its relationship with the pharmaceutical industry. Therefore, the text was guided by the desire to answer the following question: is the experience of regulation of the National Health Surveillance Agency able to cope with the adverse scenario created by the world crisis, especially with regard to the pharmaceutical industry? The main conclusion of this study is that despite the many challenges to be overcome by the National Sanitary Surveillance Agency in Brazil today, the experience of regulation has made good progress in this decade. A further finding is that these developments were, for the pharmaceutical industry, a protection against the adverse situation created by the global crisis. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
36. X-RAY PROPERTIES OF THE FIRST SUNYAEV-ZEL'DOVICH EFFECT SELECTED GALAXY CLUSTER SAMPLE FROM THE SOUTH POLE TELESCOPE.
- Author
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ANDERSSON, K., BENSON, B. A., ADE, P. A. R., AIRD, K. A., ARMSTRONG, B., BAUTZ, M., BLEEM, L. E., BRODWIN, M., CARLSTROM, J. E., CHANG, C. L., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DESAI, S., DOBBS, M. A., DUDLEY, J. P., FOLEY, R. J., FORMAN, W. R., GARMIRE, G., and GEORGE, E. M.
- Subjects
GALAXY clusters ,X-ray astronomy ,COSMIC background radiation ,TELESCOPES ,REDSHIFT - Abstract
We present results of X-ray observations of a sample of 15 clusters selected via their imprint on the cosmic microwave background from the thermal Sunyaev-Zel'dovich (SZ) effect. These clusters are a subset of the first SZ-selected cluster catalog, obtained from observations of 178 deg² of sky surveyed by the South Pole Telescope (SPT). Using X-ray observations with Chandra and XMM-Newton, we estimate the temperature, T
X , and mass, Mg , of the intracluster medium within r500 for each cluster. From these, we calculate YX = Mg TX and estimate the total cluster mass using an M500 -YX scaling relation measured from previous X-ray studies. The integrated Comptonization, YSZ . is derived from the SZ measurements, using additional information from the X-ray-measured gas density profiles and a universal temperature profile. We calculate scaling relations between the X-ray and SZ observables and find results generally consistent with other measurements and the expectations from simple self-similar behavior. Specifically, we fit a YSZ -YX relation and find a normalization of 0.82 ± 0.07, marginally consistent with the predicted ratio of YSZ /YX - 0.91 ± 0.01 that would be expected from the density and temperature models used in this work. Using the YX -derived mass estimates, we fit a YSZ -M500 relation and find a slope consistent with the self-similar expectation of YSZ ∝ M5/3 with a normalization consistent with predictions from other X-ray studies. We find that the SZ mass estimates, derived from cosmological simulations of the SPT survey, are lower by a factor of 0.78 ± 0.06 relative to the X-ray mass estimates. This offset is at a level of 1.3σ when considering the ~15% systematic uncertainty for the simulation-based SZ masses. Overall, the X-ray measurements confirm that the scaling relations of the SZ-selected clusters are consistent with the properties of other X-ray-selected samples of massive clusters, even allowing for the broad redshift range (0.29 < z < 1.08) of the sample. [ABSTRACT FROM AUTHOR]- Published
- 2011
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- View/download PDF
37. IMPROVED CONSTRAINTS ON COSMIC MICROWAVE BACKGROUND SECONDARY ANISOTROPIES FROM THE COMPLETE 2008 SOUTH POLE TELESCOPE DATA.
- Author
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SHIROKOFF, E., REICHARDT, C. L., SHAW, L., MILLEA, M., ADE, P. A. R., AIRD, K. A., BENSON, B. A., BLEEM, L. E., CARLSTROM, J. E., CHANG, C. L., CHO, H. M., CRAWFORD, T. M., CRITES, A. T., DE HAAN, T., DOBBS, M. A., DUDLEY, J., GEORGE, E. M., HALVERSON, N. W., HOLDER, G. P., and HOLZAPFEL, W. L.
- Subjects
COSMIC background radiation ,TELESCOPES ,ANISOTROPY ,GALAXY spectra ,ASTRONOMICAL observations - Abstract
We report measurements of the cosmic microwave background (CMB) power spectrum from the complete 2008 South Pole Telescope (SPT) data set. We analyze twice as much data as the first SPT power spectrum analysis, using an improved cosmological parameter estimator which fits multi-frequency models to the SPT 150 and 220 GHz bandpowers. We find an excellent fit to the measured bandpowers with a model that includes lensed primary CMB anisotropy, secondary thermal (tSZ) and kinetic (kSZ) Sunyaev-Zel'dovich anisotropies, unclustered synchrotron point sources, and clustered dusty point sources. In addition to measuring the power spectrum of dusty galaxies at high signal-to-noise, the data primarily constrain a linear combination of the kSZ and tSZ anisotropy contributions at 150 GHz and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. The 95% confidence upper limits on secondary anisotropy power are Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. We also consider the potential correlation of dusty and tSZ sources and find it incapable of relaxing the tSZ upper limit. These results increase the significance of the lower than expected tSZ amplitude previously determined from SPT power spectrum measurements. We find that models including non-thermal pressure support in groups and clusters predict tSZ power in better agreement with the SPT data. Combining the tSZ power measurement with primary CMB data halves the statistical uncertainty on or8. However, the preferred value of σ
8 varies significantly between tSZ models. Improved constraints on cosmological parameters from tSZ power spectrum measurements require continued progress in the modeling of the tSZ power. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
38. Progress on ANL/KICP Bolometers for SPTpol.
- Author
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Crites, A. T., Benson, B. A., Bleem, L., Carlstrom, J. E., Chang, C. L., Datesman, A., Divan, R., George, E. M., Holzapfel, W. L., Lee, A., Lueker, M., McMahon, J. J., Mehl, J., Meyer, S. S., Montroy, T., Natoli, T., Novosad, V., Pearson, J., Ruhl, J., and Sayre, J.
- Subjects
BOLOMETERS ,OPTICAL measurements ,OPTICAL detectors ,MICROFABRICATION ,TEMPERATURE measurements ,COSMIC background radiation - Abstract
We present progress on Argonne/KICP TES bolometers fabricated at Argonne National Labs. These detectors will be used to measure the polarization of the Cosmic Microwave Background radiation with SPTpol. The sensors are bolometers consisting of a Mo/Au transition edge sensors (TES) suspended on silicon nitride with a gold bar absorber to couple radiation to the device. We present optical measurements and thermal characterizations of prototype devices. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
39. Stability of Al-Mn Transition Edge Sensors for Frequency Domain Multiplexing.
- Author
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Hubmayr, J., Austermann, J. E., Beall, J. A., Becker, D., Bennett, D. A., Benson, B. A., Bleem, L. E., Chang, C. L., Carlstrom, J. E., Cho, H.-M., Crites, A. T., Dobbs, M., Everett, W., George, E. M., Holzapfel, W. L., Halverson, N. W., Henning, J. W., Hilton, G. C., Irwin, K. D., and Li, D.
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MULTIPLEXING ,STABILITY (Mechanics) ,BOLOMETERS ,MANGANESE alloys ,TEMPERATURE measurements ,POLARISCOPE ,INTEGRATED circuits ,MICROFABRICATION - Abstract
We are developing arrays of 150 GHz transition edge sensor (TES) polarimeters for the South Pole Telescope polarimeter (SPTpol). Prototype devices use an aluminum manganese (Al-Mn) alloy TES with a normal resistance Rn suited to frequency domain multiplexing (fMUX) used in SPTpol. Using the fMUX readout, the devices exhibit noise performance consistent with expectations when R>0.8Rn. Below 0.8Rn, the detectors have high loopgain and become unstable, which is predicted by use of a compound TES model. We address this issue in a recent fabrication with increased TES heat capacity and normal metal structures on the TES to tune the temperature sensitivity. [ABSTRACT FROM AUTHOR]
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- 2011
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40. EXTRAGALACTIC MILLIMETER-WAVE SOURCES IN SOUTH POLE TELESCOPE SURVEY DATA: SOURCE COUNTS, CATALOG, AND STATISTICS FOR AN 87 SQUARE-DEGREE FIELD.
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Vieira, J. D., Crawford, T. M., Switzer, E. R., Ade, P. A. R., Aird, K. A., Ashby, M. L. N., Benson, B. A., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crites, A. T., Haan, T. de, Dobbs, M. A., Everett, W., George, E. M., Gladders, M., Hall, N. R., and Halverson, N. W.
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- 2010
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41. SUNYAEV-ZEL’DOVICH CLUSTER PROFILES MEASURED WITH THE SOUTH POLE TELESCOPE.
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Plagge, T., Benson, B. A., Ade, P. A. R., Aird, K. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H.-M., Crawford, T. M., Crites, A. T., Haan, T. de, Dobbs, M. A., George, E. M., Hall, N. R., Halverson, N. W., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Joy, M., and Keisler, R.
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- 2010
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42. Galaxy Clusters Discovered via the Sunyaev-Zel'dovich Effect in the 2500-square-degree SPT-SZ survey
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Bleem, L. E., Stalder, Brian A, de Haan, T., Aird, K. A., Allen, S. W., Applegate, D. E., Ashby, Matthew L N, Bautz, M., Bayliss, Matthew, Benson, B. A., Bocquet, S., Brodwin, M., Carlstrom, J. E., Chang, C. L., Chiu, I., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., Desai, S., Dietrich, J. P., Dobbs, M. A., Foley, R. J., Forman, William R., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Hennig, C., Hoekstra, H., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Jones, C., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McDonald, M., McMahon, J. J., Meyer, S. S., Mocanu, L., Mohr, J. J., Murray, S. S., Padin, S., Pryke, C., Reichardt, C. L., Rest, Armin Wolfgang, Ruel, J., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Schrabback, T., Shirokoff, E., Song, J., Spieler, H. G., Stanford, S. A., Staniszewski, Z., Stark, Antony A., Story, K. T., Stubbs, Christopher William, Vanderlinde, K., Vieira, J. D., Vikhlinin, Alexey A., Williamson, R., Zahn, O., and Zenteno, A.
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cosmology: observations ,galaxies: clusters: individual ,large-scale structure of universe - Abstract
We present a catalog of galaxy clusters selected via their Sunyaev-Zel'dovich (SZ) effect signature from 2500 deg2 of South Pole Telescope (SPT) data. This work represents the complete sample of clusters detected at high significance in the 2500 deg2 SPT-SZ survey, which was completed in 2011. A total of 677 (409) cluster candidates are identified above a signal-to-noise threshold of ξ = 4.5 (5.0). Ground- and space-based optical and near-infrared (NIR) imaging confirms overdensities of similarly colored galaxies in the direction of 516 (or 76%) of the ξ > 4.5 candidates and 387 (or 95%) of the ξ > 5 candidates; the measured purity is consistent with expectations from simulations. Of these confirmed clusters, 415 were first identified in SPT data, including 251 new discoveries reported in this work. We estimate photometric redshifts for all candidates with identified optical and/or NIR counterparts; we additionally report redshifts derived from spectroscopic observations for 141 of these systems. The mass threshold of the catalog is roughly independent of redshift above z ~ 0.25 leading to a sample of massive clusters that extends to high redshift. The median mass of the sample is M 500c(ρcrit) $\sim 3.5\times 10^{14}\,M_\odot \,h_{70}^{-1}$, the median redshift is z med = 0.55, and the highest-redshift systems are at z > 1.4. The combination of large redshift extent, clean selection, and high typical mass makes this cluster sample of particular interest for cosmological analyses and studies of cluster formation and evolution., Physics
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- 2015
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43. Mass Calibration and Cosmological Analysis of the SPT-SZ Galaxy Cluster Sample Using Velocity Dispersion σ v and X-Ray Y X Measurements
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Bocquet, S., Saro, A., Mohr, J. J., Aird, K. A., Ashby, Matthew L N, Bautz, M., Bayliss, Matthew, Bazin, G., Benson, B. A., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Chiu, I., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., Desai, S., de Haan, T., Dietrich, J. P., Dobbs, M. A., Foley, R. J., Forman, William R., Gangkofner, D., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Hennig, C., Hlavacek-Larrondo, J., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Jones, C., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Marrone, D. P., McDonald, M., McMahon, J. J., Meyer, S. S., Mocanu, L., Murray, S. S., Padin, S., Pryke, C., Reichardt, C. L., Rest, Armin Wolfgang, Ruel, J., Ruhl, J. E., Saliwanchik, B. R., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Spieler, H. G., Stalder, Brian A, Stanford, S. A., Staniszewski, Z., Stark, Antony A., Story, K., Stubbs, Christopher William, Vanderlinde, K., Vieira, J. D., Vikhlinin, Alexey A., Williamson, R., Zahn, O., and Zenteno, A.
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cosmic background radiation ,cosmology: observations ,galaxies: clusters: individual ,large-scale structure of universe - Abstract
We present a velocity-dispersion-based mass calibration of the South Pole Telescope Sunyaev-Zel'dovich effect survey (SPT-SZ) galaxy cluster sample. Using a homogeneously selected sample of 100 cluster candidates from 720 deg2 of the survey along with 63 velocity dispersion (σ v ) and 16 X-ray Y X measurements of sample clusters, we simultaneously calibrate the mass-observable relation and constrain cosmological parameters. Our method accounts for cluster selection, cosmological sensitivity, and uncertainties in the mass calibrators. The calibrations using σ v and Y X are consistent at the 0.6σ level, with the σ v calibration preferring ~16% higher masses. We use the full SPTCL data set (SZ clusters+σ v +Y X) to measure σ8(Ωm/0.27)0.3 = 0.809 ± 0.036 within a flat ΛCDM model. The SPT cluster abundance is lower than preferred by either the WMAP9 or Planck+WMAP9 polarization (WP) data, but assuming that the sum of the neutrino masses is ∑m ν = 0.06 eV, we find the data sets to be consistent at the 1.0σ level for WMAP9 and 1.5σ for Planck+WP. Allowing for larger ∑m ν further reconciles the results. When we combine the SPTCL and Planck+WP data sets with information from baryon acoustic oscillations and Type Ia supernovae, the preferred cluster masses are 1.9σ higher than the Y X calibration and 0.8σ higher than the σ v calibration. Given the scale of these shifts (~44% and ~23% in mass, respectively), we execute a goodness-of-fit test; it reveals no tension, indicating that the best-fit model provides an adequate description of the data. Using the multi-probe data set, we measure Ωm = 0.299 ± 0.009 and σ8 = 0.829 ± 0.011. Within a νCDM model we find ∑m ν = 0.148 ± 0.081 eV. We present a consistency test of the cosmic growth rate using SPT clusters. Allowing both the growth index γ and the dark energy equation-of-state parameter w to vary, we find γ = 0.73 ± 0.28 and w = –1.007 ± 0.065, demonstrating that the expansion and the growth histories are consistent with a ΛCDM universe (γ = 0.55; w = –1)., Astronomy
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- 2015
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44. Measurement of Galaxy Cluster Integrated Comptonization and Mass Scaling Relations With the South Pole Telescope
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Saliwanchik, B. R., Montroy, T. E., Aird, K. A., Bayliss, Matthew, Benson, B. A., Bleem, L. E., Bocquet, S., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Foley, R. J., Forman, William R., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Hlavacek-Larrondo, J., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Jones, C., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McDonald, M., McMahon, J. J., Mehl, J., Meyer, S. S., Mocanu, L., Mohr, J. J., Murray, S, Nurgaliev, D, Padin, S., Patej, Anna, Pryke, Clement L., Reichardt, C. L., Rest, A., Ruel, J, Ruhl, J. E., Saro, A., Sayre, J. T., Schaffer, K. K., Shirokoff, E., Spieler, H. G., Stalder, Brian A, Stanford, S. A., Staniszewski, Z., Stark, Antony A., Story, K., Stubbs, Christopher William, Vanderlinde, K., Vieira, J. D., Vikhlinin, Alexey A., Williamson, R., Zahn, O., and Zenteno, A.
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methods: data analysis ,galaxies: clusters ,X-rays: galaxies: clusters - Abstract
We describe a method for measuring the integrated Comptonization (Y SZ) of clusters of galaxies from measurements of the Sunyaev-Zel'dovich (SZ) effect in multiple frequency bands and use this method to characterize a sample of galaxy clusters detected in the South Pole Telescope (SPT) data. We use a Markov Chain Monte Carlo method to fit a β-model source profile and integrate Y SZ within an angular aperture on the sky. In simulated observations of an SPT-like survey that include cosmic microwave background anisotropy, point sources, and atmospheric and instrumental noise at typical SPT-SZ survey levels, we show that we can accurately recover β-model parameters for inputted clusters. We measure Y SZ for simulated semi-analytic clusters and find that Y SZ is most accurately determined in an angular aperture comparable to the SPT beam size. We demonstrate the utility of this method to measure Y SZ and to constrain mass scaling relations using X-ray mass estimates for a sample of 18 galaxy clusters from the SPT-SZ survey. Measuring Y SZ within a 0farcm75 radius aperture, we find an intrinsic log-normal scatter of 21% ± 11% in Y SZ at a fixed mass. Measuring Y SZ within a 0.3 Mpc projected radius (equivalent to 0farcm75 at the survey median redshift z = 0.6), we find a scatter of 26% ± 9%. Prior to this study, the SPT observable found to have the lowest scatter with mass was cluster detection significance. We demonstrate, from both simulations and SPT observed clusters that Y SZ measured within an aperture comparable to the SPT beam size is equivalent, in terms of scatter with cluster mass, to SPT cluster detection significance., Astronomy, Physics
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- 2015
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45. The Redshift Evolution of the Mean Temperature, Pressure, and Entropy Profiles in 80 SPT-Selected Galaxy Clusters
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McDonald, M., Benson, B. A., Vikhlinin, Alexey A., Aird, K. A., Allen, S. W., Bautz, Marshall William, Bayliss, Matthew, Bleem, L. E., Bocquet, S., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, Hyunjii, Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Dobbs, M. A., Foley, R. J., Forman, William R., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Hlavacek-Larrondo, J., Holder, G. P., Holzapfel, W. L., Hrubes, J. D., Jones, Christine M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McMahon, J, Meyer, S. S., Miller, Eric, Mocanu, L., Mohr, J. J., Murray, S. S., Padin, S., Pryke, C., Reichardt, C. L., Rest, Armin Wolfgang, Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, James Edward, Schaffer, K. K., Shirokoff, E., Spieler, H. G., Stalder, Brian A, Stanford, S. A., Staniszewski, Z., Stark, Aaron William, Story, K. T., Stubbs, Christopher William, Vanderlinde, K., Vieira, J. D., Williamson, R., Zahn, O., and Zenteno, A.
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galaxies ,clusters ,general - galaxies ,clusters: intracluster medium - cosmology ,early universe - X-Rays - Abstract
We present the results of an X-ray analysis of 80 galaxy clusters selected in the 2500 deg2 South Pole Telescope survey and observed with the Chandra X-ray Observatory. We divide the full sample into subsamples of ∼20 clusters based on redshift and central density, performing a joint X-ray spectral fit to all clusters in a subsample simultaneously, assuming self-similarity of the temperature profile. This approach allows us to constrain the shape of the temperature profile over 0 < r < 1.5R500, which would be impossible on a per-cluster basis, since the observations of individual clusters have, on average, 2000 X-ray counts. The results presented here represent the first constraints on the evolution of the average temperature profile from z = 0 to z = 1.2. We find that high-z (0.6 < z < 1.2) clusters are slightly (∼30%) cooler both in the inner (r < 0.1R500) and outer (r > R500) regions than their low-z (0.3 < z < 0.6) counterparts. Combining the average temperature profile with measured gas density profiles from our earlier work, we infer the average pressure and entropy profiles for each subsample. Confirming earlier results from this data set, we find an absence of strong cool cores at high z, manifested in this analysis as a significantly lower observed pressure in the central 0.1R500 of the high-z cool-core subset of clusters compared to the low-z cool-core subset. Overall, our observed pressure profiles agree well with earlier lower-redshift measurements, suggesting minimal redshift evolution in the pressure profile outside of the core. We find no measurable redshift evolution in the entropy profile at r . 0.7R500 – this may reflect a long-standing balance between cooling and feedback over long timescales and large physical scales. We observe a slight flattening of the entropy profile at r & R500 in our high-z subsample. This flattening is consistent with a temperature bias due to the enhanced (∼3×) rate at which group-mass (∼2 keV) halos, which would go undetected at our survey depth, are accreting onto the cluster at z ∼ 1. This work demonstrates a powerful method for inferring spatially-resolved cluster properties in the case where individual cluster signal-to-noise is low, but the number of observed clusters is high., Physics
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- 2014
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46. Cosmological Constraints from Sunyaev-Zel'dovich-selected Clusters with X-Ray Observations in the First 178 deg2 of the South Pole Telescope Survey
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Benson, B. A., de Haan, T., Dudley, J. P., Reichardt, C. L., Aird, K. A., Andersson, K., Armstrong, R., Ashby, Matthew L N, Bautz, M., Bayliss, Matthew, Bazin, G., Bleem, L. E., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., Desai, S., Dobbs, M. A., Foley, R. J., Forman, William R., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Harrington, N., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McDonald, M., McMahon, J. J., Mehl, J., Meyer, S. S., Mocanu, L., Mohr, J. J., Montroy, T. E., Murray, S. S., Natoli, T., Padin, S., Plagge, T., Pryke, C., Rest, A., Ruel, Jonathan, Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Shaw, L., Shirokoff, E., Song, J., Spieler, H. G., Stalder, Brian A, Staniszewski, Z., Stark, Antony A., Story, K., Stubbs, Christopher William, Suhada, R., van Engelen, A., Vanderlinde, K., Vieira, J. D., Viklinin, Alexey A., Williamson, R., Zahn, O., and Zenteno, A.
- Abstract
We use measurements from the South Pole Telescope (SPT) Sunyaev-Zel'dovich (SZ) cluster survey in combination with X-ray measurements to constrain cosmological parameters. We present a statistical method that fits for the scaling relations of the SZ and X-ray cluster observables with mass while jointly fitting for cosmology. The method is generalizable to multiple cluster observables, and self-consistently accounts for the effects of the cluster selection and uncertainties in cluster mass calibration on the derived cosmological constraints. We apply this method to a data set consisting of an SZ-selected catalog of 18 galaxy clusters at z > 0.3 from the first 178 deg2 of the 2500 deg2 SPT-SZ survey, with 14 clusters having X-ray observations from either Chandra or XMM-Newton. Assuming a spatially flat ΛCDM cosmological model, we find the SPT cluster sample constrains σ8(Ω m /0.25)0.30 = 0.785 ± 0.037. In combination with measurements of the cosmic microwave background (CMB) power spectrum from the SPT and the seven-year Wilkinson Microwave Anisotropy Probe data, the SPT cluster sample constrains σ8 = 0.795 ± 0.016 and Ω m = 0.255 ± 0.016, a factor of 1.5 improvement on each parameter over the CMB data alone. We consider several extensions beyond the ΛCDM model by including the following as free parameters: the dark energy equation of state (w), the sum of the neutrino masses (Σm ν), the effective number of relativistic species (N eff), and a primordial non-Gaussianity (f NL). We find that adding the SPT cluster data significantly improves the constraints on w and Σm ν beyond those found when using measurements of the CMB, supernovae, baryon acoustic oscillations, and the Hubble constant. Considering each extension independently, we best constrain w = –0.973 ± 0.063 and the sum of neutrino masses Σm ν < 0.28 eV at 95% confidence, a factor of 1.25 and 1.4 improvement, respectively, over the constraints without clusters. Assuming a ΛCDM model with a free N eff and Σm ν, we measure N eff = 3.91 ± 0.42 and constrain Σm ν < 0.63 eV at 95% confidence. We also use the SPT cluster sample to constrain f NL = –220 ± 317, consistent with zero primordial non-Gaussianity. Finally, we discuss the current systematic limitations due to the cluster mass calibration, and future improvements for the recently completed 2500 deg2 SPT-SZ survey. The survey has detected ~500 clusters with a median redshift of ~0.5 and a median mass of ~2.3 × 1014 M ☉ h –1 and, when combined with an improved cluster mass calibration and existing external cosmological data sets will significantly improve constraints on w., Astronomy, Physics
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- 2013
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47. Galaxy clusters discovered via the Sunyaev-Zel'dovich effect in the first 720 square degrees of the South Pole Telescope survey
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Reichardt, C. L., Stalder, B., Bleem, L. E., Montroy, T. E., Aird, K. A., Andersson, K., Armstrong, R., Ashby, M. L. N., Bautz, M., Bayliss, Matthew, Bazin, G., Benson, B. A., Brodwin, M., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Foley, R. J., Forman, W. R., George, E. M., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Harrington, N. L., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McDonald, M., McMahon, J. J., Mehl, J., Meyer, S. S., Mocanu, L., Mohr, J. J., Murray, S. S., Natoli, T., Padin, S., Plagge, T., Pryke, C., Rest, A., Ruel, J., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Shaw, L., Shirokoff, E., Song, J., Spieler, H. G., Staniszewski, Z., Stark, A. A., Story, K., Stubbs, Christopher William, Suhada, R., van Engelen, A., Vanderlinde, K., Vieira, J. D., Vikhlinin, A., Williamson, R., Zahn, O., and Zenteno, A.
- Abstract
We present a catalog of galaxy cluster candidates, selected through their Sunyaev-Zel'dovich (SZ) effect signature in the first 720 deg2 of the South Pole Telescope (SPT) survey. This area was mapped with the SPT in the 2008 and 2009 austral winters to a depth of ~18 μKCMB-arcmin at 150 GHz; 550 deg2 of it was also mapped to ~44 μKCMB-arcmin at 95 GHz. Based on optical imaging of all 224 candidates and near-infrared imaging of the majority of candidates, we have found optical and/or infrared counterparts for 158, which we then classify as confirmed galaxy clusters. Of these 158 clusters, 135 were first identified as clusters in SPT data, including 117 new discoveries reported in this work. This catalog triples the number of confirmed galaxy clusters discovered through the SZ effect. We report photometrically derived (and in some cases spectroscopic) redshifts for confirmed clusters and redshift lower limits for the remaining candidates. The catalog extends to high redshift with a median redshift of z = 0.55 and maximum confirmed redshift of z = 1.37. Forty-five of the clusters have counterparts in the ROSAT bright or faint source catalogs from which we estimate X-ray fluxes. Based on simulations, we expect the catalog to be nearly 100% complete above M 500 ≈ 5 × 1014 M ☉ h –1 70 at z gsim 0.6. There are 121 candidates detected at signal-to-noise ratio greater than five, at which the catalog purity is measured to be 95%. From this high-purity subsample, we exclude the z < 0.3 clusters and use the remaining 100 candidates to improve cosmological constraints following the method presented by Benson et al. Adding the cluster data to CMB + BAO + H 0 data leads to a preference for non-zero neutrino masses while only slightly reducing the upper limit on the sum of neutrino masses to ∑m ν < 0.38 eV (95% CL). For a spatially flat wCDM cosmological model, the addition of this catalog to the CMB + BAO + H 0 + SNe results yields σ8 = 0.807 ± 0.027 and w = –1.010 ± 0.058, improving the constraints on these parameters by a factor of 1.4 and 1.3, respectively. The larger cluster catalog presented in this work leads to slight improvements in cosmological constraints from those presented by Benson et al. These cosmological constraints are currently limited by uncertainty in the cluster mass calibration, not the size or quality of the cluster catalog. A multi-wavelength observation program to improve the cluster mass calibration will make it possible to realize the full potential of the final 2500 deg2 SPT cluster catalog to constrain cosmology., Astronomy, Physics
- Published
- 2013
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48. SPT-CL J0205–5829: A z = 1.32 Evolved Massive Galaxy Cluster in the South Pole Telescope Sunyaev-Zel'dovich Effect Survey
- Author
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Stalder, Brian A, Ruel, Jonathan, Šuhada, R., Brodwin, M., Aird, K. A., Andersson, K., Armstrong, R., Ashby, Matthew L N, Bautz, M., Bayliss, Matthew, Bazin, G., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. M., Clocchiatti, A., Crawford, T. M., Crites, A. T., de Haan, T., Desai, S., Dobbs, M. A., Dudley, J. P., Foley, R. J., Forman, William R., George, E. M., Gettings, D., Gladders, M. D., Gonzalez, A. H., Halverson, N. W., Harrington, N. L., High, F. W., Holder, G. P., Holzapfel, W. L., Hoover, S., Hrubes, J. D., Jones, C., Joy, M., Keisler, R., Knox, L., Lee, A. T., Leitch, E. M., Liu, J., Lueker, M., Luong-Van, D., Mantz, A., Marrone, D. P., McDonald, M., McMahon, J. J., Mehl, J., Meyer, S. S., Mocanu, L., Mohr, J. J., Montroy, T. E., Murray, Stephen S., Natoli, T., Nurgaliev, Daniyar Rashidovich, Padin, S., Plagge, T., Pryke, C., Reichardt, C. L., Rest, A., Ruhl, J. E., Saliwanchik, B. R., Saro, A., Sayre, J. T., Schaffer, K. K., Shaw, L., Shirokoff, E., Song, J., Spieler, H. G., Stanford, S. A., Staniszewski, Z., Stark, Antony A., Story, K., Stubbs, Christopher William, van Engelen, A., Vanderlinde, K., Vieira, J. D., Vikhlinin, Alexey A., Williamson, R., Zahn, O., and Zenteno, A.
- Subjects
early universe ,galaxies: clusters: individual (SPT-CL J0205–5829) ,galaxies: evolution ,galaxies: formation ,large-scale structure of universe - Abstract
The galaxy cluster SPT-CL J0205–5829 currently has the highest spectroscopically confirmed redshift, z = 1.322, in the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey. XMM-Newton observations measure a core-excluded temperature of TX = 8.7+1.0 –0.8 keV producing a mass estimate that is consistent with the Sunyaev-Zel'dovich-derived mass. The combined SZ and X-ray mass estimate of M 500 = (4.8 ± 0.8) × 1014 h –1 70 M ☉ makes it the most massive known SZ-selected galaxy cluster at z > 1.2 and the second most massive at z > 1. Using optical and infrared observations, we find that the brightest galaxies in SPT-CL J0205–5829 are already well evolved by the time the universe was <5 Gyr old, with stellar population ages >≈ Gyr, and low rates of star formation (<0.5 M ☉ yr–1). We find that, despite the high redshift and mass, the existence of SPT-CL J0205–5829 is not surprising given a flat ΛCDM cosmology with Gaussian initial perturbations. The a priori chance of finding a cluster of similar rarity (or rarer) in a survey the size of the 2500 deg2 SPT-SZ survey is 69%.
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- 2013
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49. Al-Mn Transition Edge Sensors for Cosmic Microwave Background Polarimeters.
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Schmidt, D. R., Cho, H.-M., Hubmayr, J., Lowell, P., Niemack, M. D., O'Neil, G. C., Ullom, J. N., Yoon, K. W., Irwin, K. D., Holzapfel, W. L., Lueker, M., George, E. M., and Shirokoff, E.
- Subjects
COSMIC background radiation ,POLARISCOPE ,ORTHOGONAL frequency division multiplexing ,MANGANESE compounds ,BANDWIDTHS ,SUPERCONDUCTING quantum interference devices ,TEMPERATURE measurements ,OPTICAL detectors ,THIN films - Abstract
Superconducting transition edge sensors (TES) require superconducting films with transition temperatures (Tc) and properties that can be tailored to the particular requirements of individual applications. We have been developing Al-Mn films with a tunable Tc. The addition of Mn to Al suppresses Tc, but does not significantly broaden the superconducting density of states of the Al. We can produce films with Tc from below 50 mK to 1.4 K through adjustment of the Mn concentration. Since this is a bulk effect, Tc is not as dependent on precise control of film thickness as in the standard bilayer approach for TESs. We have previously used Al-Mn to fabricate TES sensors for x-ray microcalorimeters targeted for read-out with time division SQUID multiplexing schemes. In this work, we explore the properties of Al-Mn in a regime well suited for frequency division multiplexing. We have also fabricated prototype Al-Mn cosmic microwave background polarimeters for the South Pole Telescope and will show initial measurements of these sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
50. Consistency of cosmic microwave background temperature measurements in three frequency bands in the 2500-square-degree SPT-SZ survey.
- Author
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Mocanu, L. M., Crawford, T. M., Aylor, K., Benson, B. A., Bleem, L. E., Carlstrom, J. E., Chang, C. L., Cho, H. -M, Chown, R., Crites, A. T., de Haan, T., Dobbs, M. A., Everett, W. B., George, E. M., Halverson, N. W., Harrington, N. L., Henning, J. W., Holder, G. P., Holzapfel, W. L., and Hou, Z.
- Published
- 2019
- Full Text
- View/download PDF
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