Publications

OBJECTIVES: To identify the barriers, facilitators, and potential better practices to achieving physician-system alignment. METHODS: Interviews using a semi-structured, open-ended protocol were conducted during a total of 18 site visits, each usually 2 days in length, covering multiple topics of physician group-system alignment. Interviews were conducted with members of the target physician group, key leaders of the health care system, and representatives of physicians not in the target group. The summary of the interviews for each of the site visits was analyzed to determine barriers, facilitators, and better practices for achieving more effective relationships between physician groups and health care systems. RESULTS: A number of barriers to more effective relationships between physician groups and health systems were identified. Barriers related to environment, culture, and information systems were most prevalent. Other major general areas of barriers encountered were physician leadership, group-system relationship, compensation and productivity, care management practices, group strategy, and accountability. Examples of practices that may help to resolve some of these issues were also identified. CONCLUSIONS: Physician-system relationships can and do cause problems for improving health care. The evidence from the conducted site visits suggests that specific strategies may help improve these relationships but more research is needed in order assess the actual impact of these strategies.

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

view Abstract Citations (37) References (46) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Simultaneous ROSAT, GINGA, VLA, IUE, and Optical Observations of the Bright Quasar H1821+643 Kolman, Michiel ; Halpern, Jules P. ; Shrader, Chris R. ; Filippenko, Alexei V. ; Fink, Henner H. ; Schaeidt, Stephan G. Abstract We report on the first simultaneous optical, UV, and X-ray spectroscopy of the low-redshift (z = 0.297), high-luminosity QSO H 1821 + 643. This multiwavelength campaign was complemented by optical imaging and radio mapping with the VLA. Although there was no significant variability during the 40 day monitoring period in either the UV or X-ray bands, a number of new results were obtained. There is significant variability in the optical, UV, and X-ray bands on time scales of years, both in flux level and spectral shape. In the co-added ultraviolet spectrum we detected a Lyman-α absorption line at z = 0.225. In the radio map the QSO is extended in the north-south direction at 20 cm, and can be resolved into two separate components at 6 cm. In the ROSAT data we separated (both spatially and spectroscopically) the emission originating in H1821 + 643 from the nearby hot white dwarf K1 - 16, and thus we isolated the intrinsic soft X-ray excess in the QSO. The IUE and ROSAT data were combined with new optical spectroscopy and hard X-ray data from Ginga, to reveal a strong optical/UV bump with a flat slope (α~ -0.96, f_v_ is proportional to Valpha^) in the UV, a steep soft X-ray excess (α~ -4) between ~0.15 keV and ~0.5 keV, and a typical hard X-ray slope of α~ -0.8 extending up to 10 keV. While the optical/UV bump and the soft X-ray excess can each be fit satisfactorily with standard accretion disk models, a joint fit to the optical/UV/X-ray bump cannot be achieved. This suggests that either the optical/UV or the soft X-ray emission do not arise in an accretion disk, or that the standard bare disk model should be modified (possibly by inclusion of electron scattering) to account for both the strong, flat UV emission and the steep, soft X-ray excess. Publication: The Astrophysical Journal Pub Date: January 1993 DOI: 10.1086/172153 Bibcode: 1993ApJ...402..514K Keywords: Accretion Disks; Iue; Quasars; Rosat Mission; Spaceborne Astronomy; Very Large Array (Vla); Astronomical Models; Astronomical Spectroscopy; Emission Spectra; Red Shift; Spectral Energy Distribution; Ultraviolet Spectroscopy; X Ray Spectroscopy; Astrophysics; RADIO CONTINUUM: GALAXIES; ULTRAVIOLET: GALAXIES; GALAXIES: QUASARS: INDIVIDUAL ALPHANUMERIC: H1821; 643; X-RAYS: GALAXIES full text sources ADS | data products SIMBAD (8) NED (2) MAST (1) INES (1)

The objective of multi-use telescopes is to reduce the initial and operational costs of space telescopes to the point where a fair number of telescopes, a dozen or so, would be affordable. The basic approach is to develop a common telescope, control system, and power and communications subsystem that can be used with a wide variety of instrument payloads, i.e., imaging CCD cameras, photometers, spectrographs, etc. By having such a multi-use and multi-user telescope, a common practice for earth-based telescopes, development cost can be shared across many telescopes, and the telescopes can be produced in economical batches.

In this work, the corrosion behavior of Mg-SiO2 nanocomposites, fabricated by powder metallurgy coupled with hybrid microwave sintering and subsequent hot extrusion, was investigated using electrochemical, hydrogen evolution and weight loss measurements. Localized intergranular corrosion behavior was analyzed based on microstructural characteristics, which were characterized by scanning electron microscopy, energy-dispersive x-ray spectroscopy, and high-resolution transmission electron microscopy (HRTEM). In particular, copious numbers of Mg/MgO misfit dislocations were identified at the interface between the matrix Mg and SiO2 nanoparticles; indeed, first principles calculations revealed that the MgO/Mg interfaces were relatively weakly bonded as compared to the close-packed interfacial Mg(0001)//MgO(111) structure. Using geometrical phase analysis of the HRTEM images to determine the lattice strains in the Mg/MgO interfacial area, we conclude that the highly strained and weakly bonded Mg/MgO interfaces act to promote significant localized dissolution and thus play a dominant role in intensifying intergranular corrosion in these nanocomposites.

This paper is focused not on the Internet architecture - as defined by layering, the narrow waist of IP, and other core design principles - but on the Internet infrastructure, as embodied in the technologies and organizations that provide Internet service. In this paper we discuss both the challenges and the opportunities that make this an auspicious time to revisit how we might best structure the Internet's infrastructure. Currently, the tasks of transit-between-domains and last-mile-delivery are jointly handled by a set of ISPs who interconnect through BGP. In this paper we propose cleanly separating these two tasks. For transit, we propose the creation of a "public option" for the Internet's core backbone. This public option core, which complements rather than replaces the backbones used by large-scale ISPs, would (i) run an open market for backbone bandwidth so it could leverage links offered by third-parties, and (ii) structure its terms-of-service to enforce network neutrality so as to encourage competition and reduce the advantage of large incumbents.

Abstract Light echoes give us a unique perspective on the nature of supernovae and nonterminal stellar explosions. Spectroscopy of light echoes can reveal details on the kinematics of the ejecta, probe asymmetry, and reveal details of ejecta interaction with circumstellar matter, thus expanding our understanding of these transient events. However, the spectral features arise from a complex interplay between the source photons, the reflecting dust geometry, and the instrumental setup and observing conditions. In this work, we present an improved method for modeling these effects in light echo spectra, one that relaxes the simplifying assumption of a light-curve-weighted sum, and instead estimates the true relative contribution of each phase of a transient event to the observed spectrum. We discuss our logic, the gains we obtain over light echo analysis methods used in the past, and prospects for further improvements. Lastly, we show how the new method improves our analysis of echoes from Tycho’s supernova (SN 1572) as an example.