The FIRST-2MASS Red Quasar Survey

Combining radio observations with optical and infrared color selection -- demonstrated in our pilot study to be an efficient selection algorithm for finding red quasars -- we have obtained optical and infrared spectroscopy for 120 objects in a complete sample of 156 candidates from a sky area of 2716 square degrees. Consistent with our initial results, we find our selection criteria -- J-K>1.7, R-K>4.0 -- yield a ~50% success rate for discovering quasars substantially redder than those found in optical surveys. Comparison with UVX- and optical color-selected samples shows that >~ 10% of the quasars are missed in a magnitude-limited survey. Simultaneous two-frequency radio observations for part of the sample indicate that a synchrotron continuum component is ruled out as a significant contributor to reddening the quasars' spectra. We go on to estimate extinctions for our objects assuming their red colors are caused by dust. Continuum fits and Balmer decrements suggest E(B-V) values ranging from near zero to 2.5 magnitudes. Correcting the K-band magnitudes for these extinctions, we find that for K <= 14.0, red quasars make up between 25% and 60% of the underlying quasar population; owing to the incompleteness of the 2MASS survey at fainter K-band magnitudes, we can only set a lower limit to the radio-detected red quasar population of >20-30%.Comment: 80 pages (single-column, preprint format) 20 figures, Accepted for publicated in Ap

User survey finds rapid evidence reviews increased uptake of evidence by Veterans Health Administration leadership to inform fast-paced health-system decision-making

Survey Instrument. Copy of survey instrument sent to operational partners. Included for audience to reference if needed. (PDF 222 kb

The Reddest Quasars

In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7-093102 is a 1 Jy source at z=2.216 and has B-K > 10, while FIRST J073820.1+275045 is a 2.5 mJy source at z=1.985 with B-K = 8.4. FIRST J073820.1+275045 has strong absorption lines of MgII and CIV in the rest frame of the quasar and is highly polarized in the rest frame ultraviolet, strongly favoring the interpretation that its red spectral energy distribution is caused by dust reddening local to the quasar. FIRST J073820.1+275045 is thus one of the few low radio-luminosity, highly dust-reddened quasars known. The available observational evidence for FIRST J013435.7-093102 leads us to conclude that it too is reddened by dust. We show that FIRST J013435.7-093102 is gravitationally lensed, increasing the number of known lensed, extremely dust-reddened quasars to at least three, including MG0414-0534 and PKS1830-211. We discuss the implications of whether these objects are reddened by dust in the host or lensing galaxies. If reddened by their local environment, then we estimate that between 10 and 20% of the radio-loud quasar population is reddened by dust in the host galaxy. The discovery of FIRST J073820.1+275045 and objects now emerging from X-ray surveys suggests the existence of an analogous radio-quiet red quasar population. Such objects will be entirely missed by standard radio or optical quasar surveys. If dust in the lensing galaxies is primarily responsible for the extreme redness of the lensed quasars, then an untold number of gravitationally lensed quasars are being overlooked.Comment: AASTEX 24 pp., 7 figs; accepted by ApJ. See also the preprint astro-ph/0107435 by Winn et al., who independently discovered that J013435.7-093102 is gravitationally lense

Bulk and Interfacial Shear Thinning of Immiscible Polymers

Nonequilibrium molecular dynamics simulations are used to study the shear thinning behavior of immiscible symmetric polymer blends. The phase separated polymers are subjected to a simple shear flow imposed by moving a wall parallel to the fluid-fluid interface. The viscosity begins to shear thin at much lower rates in the bulk than at the interface. The entire shear rate dependence of the interfacial viscosity is consistent with a shorter effective chain length $s^*$ that also describes the width of the interface. This $s^*$ is independent of chain length $N$ and is a function only of the degree of immiscibility of the two polymers. Changes in polymer conformation are studied as a function of position and shear rate.Shear thinning correlates more closely with a decrease in the component of the radius of gyration along the velocity gradient than with elongation along the flow. At the interface, this contraction of chains is independent of $N$ and consistent with the bulk behavior for chains of length $s^*$. The distribution of conformational changes along chains is also studied. Central regions begin to stretch at a shear rate that decreases with increasing $N$, while shear induced changes at the ends of chains are independent of $N$.Comment: 8 pages, 8 figure

Methods for the Drug Effectiveness Review Project

Abstract The Drug Effectiveness Review Project was initiated in 2003 in response to dramatic increases in the cost of pharmaceuticals, which lessened the purchasing power of state Medicaid budgets. A collaborative group of state Medicaid agencies and other organizations formed to commission high-quality comparative effectiveness reviews to inform evidence-based decisions about drugs that would be available to Medicaid recipients. The Project is coordinated by the Center for Evidence-based Policy (CEbP) at Oregon Health & Science University (OHSU), and the systematic reviews are undertaken by the Evidence-based Practice Centers (EPCs) at OHSU and at the University of North Carolina. The reviews adhere to high standards for comparative effectiveness reviews. Because the investigators have direct, regular communication with policy-makers, the reports have direct impact on policy and decision-making, unlike many systematic reviews. The Project was an innovator of methods to involve stakeholders and continues to develop its methods in conducting reviews that are highly relevant to policy-makers. The methods used for selecting topics, developing key questions, searching, determining eligibility of studies, assessing study quality, conducting qualitative and quantitative syntheses, rating the strength of evidence, and summarizing findings are described. In addition, our on-going interactions with the policy-makers that use the reports are described

GLIMPSE: I. A SIRTF Legacy Project to Map the Inner Galaxy

GLIMPSE (Galactic Legacy Infrared Mid-Plane Survey Extraordinaire), a SIRTF Legacy Science Program, will be a fully sampled, confusion-limited infrared survey of the inner two-thirds of the Galactic disk with a pixel resolution of \~1.2" using the Infrared Array Camera (IRAC) at 3.6, 4.5, 5.8, and 8.0 microns. The survey will cover Galactic latitudes |b| <1 degree and longitudes |l|=10 to 65 degrees (both sides of the Galactic center). The survey area contains the outer ends of the Galactic bar, the Galactic molecular ring, and the inner spiral arms. The GLIMPSE team will process these data to produce a point source catalog, a point source data archive, and a set of mosaicked images. We summarize our observing strategy, give details of our data products, and summarize some of the principal science questions that will be addressed using GLIMPSE data. Up-to-date documentation, survey progress, and information on complementary datasets are available on the GLIMPSE web site: www.astro.wisc.edu/glimpse.Comment: Description of GLIMPSE, a SIRTF Legacy project (Aug 2003 PASP, in press). Paper with full res.color figures at http://www.astro.wisc.edu/glimpse/glimpsepubs.htm

Exploring the Optical Transient Sky with the Palomar Transient Factory

The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes to years. PTF uses the CFH12k mosaic camera, with a field of view of 7.9 deg^2 and a plate scale of 1 asec/pixel, mounted on the the Palomar Observatory 48-inch Samuel Oschin Telescope. The PTF operation strategy is devised to probe the existing gaps in the transient phase space and to search for theoretically predicted, but not yet detected, phenomena, such as fallback supernovae, macronovae, .Ia supernovae and the orphan afterglows of gamma-ray bursts. PTF will also discover many new members of known source classes, from cataclysmic variables in their various avatars to supernovae and active galactic nuclei, and will provide important insights into understanding galactic dynamics (through RR Lyrae stars) and the Solar system (asteroids and near-Earth objects). The lessons that can be learned from PTF will be essential for the preparation of future large synoptic sky surveys like the Large Synoptic Survey Telescope. In this paper we present the scientific motivation for PTF and describe in detail the goals and expectations for this experiment.Comment: 15 pages, 6 figures, submitted to PAS

Reporting Discrepancies between the ClinicalTrials.gov Results Database and Peer Reviewed Publications

BACKGROUND: Result summaries are now required to be reported in ClinicalTrials.gov for many 1 trials of drugs and devices. PURPOSE: To evaluate the consistency of reporting in trials that are both registered in the ClinicalTrials.gov results database and published in the literature. DATA SOURCES: ClinicalTrials.gov results database, matched publications identified through both ClinicalTrials.gov and a manual search of two electronic databases. STUDY SELECTION: 10% random sample of Phase III or IV trials with results in the ClinicalTrials.gov results database, completed before January 1, 2009, with two or more arms. DATA EXTRACTION: One reviewer extracted data from ClinicalTrials.gov results database and matching publications. A subsample was independently verified. Basic design features and results were compared between reporting sources and discrepancies were summarized. DATA SYNTHESIS: Of 110 reviewed trials with results, most were industry-sponsored, parallel design, drug studies. The most common inconsistency was the number of secondary outcome measures reported (80%). There were 16 trials (15%) that reported the primary outcome description inconsistently and 22 (20%) in which the primary outcome value was reported inconsistently. A total of 38 trials inconsistently reported the number of individuals with a serious adverse event (SAE), of which 33 (87%) reported more SAEs in ClinicalTrials.gov. Among the 84 trials that reported SAEs in ClinicalTrials.gov, 11 publications did not mention SAEs, 5 reported SAEs as zero or not occurring, and 21 reported a different number of SAEs. In 29 trials that reported deaths in ClinicalTrials.gov, 28% differed with the matched publication. LIMITATIONS: Small sample that includes earliest results posted to the database and therefore may reflect inexperience with the submission process. CONCLUSIONS: Reporting discrepancies between the ClinicalTrials.gov results database and matching publications are common. It is unclear which reporting source contains the most accurate account of trial results. ClinicalTrials.gov may provide a more comprehensive description of trial adverse events than the publication.This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American College of Physicians and can be found at: http://annals.org/

Comparative Effectiveness Research: Challenges for Medical Journals

Editors from a number of medical journals lay out principles for journals considering publication of Comparative Effectiveness Research (CER). In order to encourage dissemination of this editorial, this article is freely available in PLoS Medicine and will be also published in Medical Decision Making, Croatian Medical Journal, The Cochrane Library, Trials, The American Journal of Managed Care, and Journal of Clinical Epidemiology

Tensile Fracture of Welded Polymer Interfaces: Miscibility, Entanglements and Crazing

Large-scale molecular simulations are performed to investigate tensile failure of polymer interfaces as a function of welding time $t$. Changes in the tensile stress, mode of failure and interfacial fracture energy $G_I$ are correlated to changes in the interfacial entanglements as determined from Primitive Path Analysis. Bulk polymers fail through craze formation, followed by craze breakdown through chain scission. At small $t$ welded interfaces are not strong enough to support craze formation and fail at small strains through chain pullout at the interface. Once chains have formed an average of about one entanglement across the interface, a stable craze is formed throughout the sample. The failure stress of the craze rises with welding time and the mode of craze breakdown changes from chain pullout to chain scission as the interface approaches bulk strength. The interfacial fracture energy $G_I$ is calculated by coupling the simulation results to a continuum fracture mechanics model. As in experiment, $G_I$ increases as $t^{1/2}$ before saturating at the average bulk fracture energy $G_b$. As in previous simulations of shear strength, saturation coincides with the recovery of the bulk entanglement density. Before saturation, $G_I$ is proportional to the areal density of interfacial entanglements. Immiscibiltiy limits interdiffusion and thus suppresses entanglements at the interface. Even small degrees of immisciblity reduce interfacial entanglements enough that failure occurs by chain pullout and $G_I \ll G_b$