We present HST ACS coronagraphic observations of HD 100546, a B9.5 star, 103 pc away from the Sun, taken in the F435W, F606W, and F814W bands. Scattered light is detected up to 14" from the star. The ...observations are consistent with the presence of an extended flattened nebula with the same inclination as the inner disk. The well-known "spiral arms" are clearly observed and trail the rotating disk material. Weaker arms never before reported are also seen. The interarm space becomes brighter, but the structures become more neutral in color at longer wavelengths, which Is not consistent with models that assume that they are due to the effects of a warped disk. Along the major disk axis, the colors of the scattered light relative to the star are Delta (F 435W - F 606W) approximately 0.0-0.2 mag and Delta (F 435W - F814W) approximately 0.5-1 mag. To explain these colors, we explore the role of asymmetric scattering, reddening, and large minimum sizes on ISM-like grains. We conclude that each of these hypotheses by itself cannot explain the colors. The disk colors are similar to those derived for Kuiper Belt objects, suggesting that the same processes responsible for their colors may be at work here. We argue that we are observing only the geometrically thick, optically thin envelope of the disk, while the optically thick disk responsible for the far-IR emission is undetected. The observed spiral arms are then structures on this envelope. The colors indicate that the extended nebulosity is not a remnant of the infalling envelope but reprocessed disk material.
Abstract Purpose Health care leaders encourage clinicians to offer portals that enable patients to access personal health records, but implementation has been a challenge. Although large integrated ...health systems have promoted use through costly advertising campaigns, other implementation methods are needed for small to medium-sized practices where most patients receive their care. Methods We conducted a mixed methods assessment of a proactive implementation strategy for a patient portal (an interactive preventive health record IPHR) offered by 8 primary care practices. The practices implemented a series of learning collaboratives with practice champions and redesigned workflow to integrate portal use into care. Practice implementation strategies, portal use, and factors influencing use were assessed prospectively. Results A proactive and customized implementation strategy designed by practices resulted in 25.6% of patients using the IPHR, with the rate increasing 1.0% per month over 31 months. Fully 23.5% of IPHR users signed up within 1 day of their office visit. Older patients and patients with comorbidities were more likely to use the IPHR, but blacks and Hispanics were less likely. Older age diminished as a factor after adjusting for comorbidities. Implementation by practice varied considerably (from 22.1% to 27.9%, P <.001) based on clinician characteristics and workflow innovations adopted by practices to enhance uptake. Conclusions By directly engaging patients to use a portal and supporting practices to integrate use into care, primary care practices can match or potentially surpass the usage rates achieved by large health systems.
Abstract Purpose Americans receive only one-half of recommended preventive services. Information technologies have been advocated to engage patients. We tested the effectiveness of an interactive ...preventive health record (IPHR) that links patients to their clinician's record, explains information in lay language, displays tailored recommendations and educational resources, and generates reminders. Methods This randomized controlled trial involved 8 primary care practices. Four thousand five hundred patients were randomly selected to receive a mailed invitation to use the IPHR or usual care. Outcomes were measured using patient surveys and electronic medical record data and included IPHR use and service delivery. Comparisons were made between invited and usual-care patients and between users and nonusers among those invited to use the IPHR. Results At 4 and 16 months, 229 (10.2%) and 378 (16.8%) of invited patients used the IPHR. The proportion of patients up-to-date with all services increased between baseline and 16 months by 3.8% among intervention patients (from 11.4% to 15.2%, P <.001) and by 1.5% among control patients (from 11.1% to 12.6%, P = .07), a difference of 2.3% ( P = .05). Greater increases were observed among patients who used the IPHR. At 16 months, 25.1% of users were up-to-date with all services, double the rate among nonusers. At 4 months, delivery of colorectal, breast, and cervical cancer screening increased by 19%, 15%, and 13%, respectively, among users. Conclusions Information systems that feature patient-centered functionality, such as the IPHR, have potential to increase preventive service delivery. Engaging more patients to use systems could have important public health benefits.
We present HST ACS observations of the most distant radio galaxy known, TN J0924-2201 at z = 5.2. This radio galaxy has six spectroscopically confirmed Lya-emitting companion galaxies and appears to ...lie within an overdense region. The radio galaxy is marginally resolved in i sub(775) and z sub(850), showing continuum emission aligned with the radio axis, similar to what is observed for lower redshift radio galaxies. Both the half-light radius and the UV star formation rate are comparable to the typical values found for Lyman break galaxies at z 6 4-5. The Lya emitters are sub-L sub(*) galaxies, with deduced star formation rates of 1-10 M sub( )yr super(-1). One of the Lya emitters is only detected in Lya. Based on the star formation rate of 63 M sub( )yr super(-1) calculated from Lya, the lack of continuum emission could be explained if the galaxy is younger than 62 Myr and is producing its first stars. Observations in V sub(606)i sub(775)z sub(850) were used to identify additional Lyman break galaxies associated with this structure. In addition to the radio galaxy, there are 22 V sub(606) break (z 6 5) galaxies with z sub(850) < 26.5 (5 s), two of which are also in the spectroscopic sample. We compare the surface density of 62 arcmin super(-2) to that of similarly selected V sub(606) dropouts extracted from GOODS and the UDF parallel fields. We find evidence for an overdensity to very high confidence (>99%), based on a counts-in-cells analysis applied to the control field. The excess suggests that the V sub(606) break objects are associated with a forming cluster around the radio galaxy.
The color-magnitude relation has been determined for the RDCS J0910+5422 cluster of galaxies at redshift z = 1.106. Cluster members were selected from the Hubble Space Telescope Advanced Camera for ...Surveys (HST ACS) images, combined with ground-based near-IR imaging and optical spectroscopy. The observed early-type color-magnitude relation (CMR) in i' sub(775) - z sub(850) versus z sub(850) shows an intrinsic scatter in color of 0.060 c 0.009 mag, within 1' from the cluster X-ray emission center. Both the elliptical and the S0 galaxies show small scatter about the CMR of 0.042 c 0.010 and 0.044 c 0.020 mag, respectively. From the scatter about the CMR, a mean luminosity-weighted age super( )> 3.3 Gyr (z sub(f) - 3) is derived for the elliptical galaxies, assuming a simple stellar population modeling (single-burst solar metallicity). Strikingly, the S0 galaxies in RDCS J0910+5422 are systematically bluer in i sub(775) - z sub(850), by 0.07 c 0.02 mag, than the ellipticals. The ellipticity distribution as a function of color indicates that the face-on S0s in this particular cluster have likely been classified as elliptical Thus, if anything, the offset in color between the elliptical and S0 populations may be even more significant. The color offset between S0 and E galaxies corresponds to an age difference of -1 Gyr for a single-burst solar-metallicity model. A solar-metallicity model with an exponential decay in star formation will reproduce the offset for an age of 3.5 Gyr; i.e., the S0s have evolved gradually from star-forming progenitors. The early-type population in this cluster appears to be still forming. The blue early-type disk galaxies in RDCS J0910+5422 likely represent the direct progenitors of the more evolved S0s that follow the same red sequence as elliptical galaxies in other clusters. Thirteen red galaxy pairs are observed, and the galaxies associated in pairs constitute 640% of the CMR galaxies in this cluster.
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