Perioperative Glycemic Management

Proposals and Goals: 1. We propose creating a standard easy to use and safe protocol for glycemic management for same day/elective surgical patients. 2. Following implementation in same day and elective surgical procedures, we propose expanding the protocol to be effective in urgent and emergent inpatient surgical procedures.https://jdc.jefferson.edu/patientsafetyposters/1068/thumbnail.jp

The Mass-to-Light Ratios of the Draco and Ursa Minor Dwarf Spheroidal Galaxies. II. The Binary Population and Its Effect in the Measured Velocity Dispersions of Dwarf Spheroidal Galaxies

We use a large set of radial velocities in the Ursa Minor and Draco dwarf spheroidal galaxies to search for binary stars and to infer the binary frequency. Of the 118 stars in our sample with multiple observations, six are velocity variables with $\chi^2$ probabilities below 0.001. We use Monte Carlo simulations that mimic our observations to determine the efficiency with which our observations find binary stars. Our best, though significantly uncertain, estimate of the binary frequency for stars near the turnoff in Draco and UMi is 0.2--0.3 per decade of period in the vicinity of periods of one year, which is 3--5$\times$ that found for the solar neighborhood. This frequency is high enough that binary stars might significantly affect the measured velocity dispersions of some dwarf spheroidal galaxies according to some previous numerical experiments. However, in the course of performing our own experiments, we discovered that this previous work had inadvertently overestimated binary orbital velocities. Our first set of simulations of the effects of binaries is based on the observed scatter in the individual velocity measurements for the multiply-observed Draco and Ursa Minor stars. This scatter is small compared to measured velocity dispersions and, so, the effect of binaries on the dispersions is slight. This result is supported by our second set of experiments, which are based on a model binary population normalized by the observed binary frequency in Draco and Ursa Minor. We conclude that binary stars have had no significant effect on the measured velocity dispersion and inferred mass-to-light ratio of any dwarf spheroidal galaxy.Comment: 33 pages, 95kb uuencoded, gzipped postscript; Accepted by Astronomical Journal; gzipped, tarred postscript of text, tables, figures available at ftp://as.arizona.edu/pub/edo (binaries_in_dsph.tar.gz

Standardized Consent Forms for Surgical Procedures: An Intervention to Improve the Resident-led Informed Consent Process

Objectives and Goals: To provide high quality, consistent consent forms for common surgical procedures and improve resident workflow by creating and implementing standardized printed consents for common surgical procedures. These consents will be used by residents consenting patients in the ED or inpatient setting. Consents shall include standardized procedure descriptions, risks and benefits of the procedure, and alternative treatment option descriptions, risks and benefitshttps://jdc.jefferson.edu/patientsafetyposters/1057/thumbnail.jp

Ambulation protocols leading to decreased postoperative complications and hospital stay

Background: In the postoperative course, patients are routinely encouraged to ambulate as frequently as possible. Typically in the hospital this can become burdensome to the staff and often becomes low priority. Patients are also not aware of the frequency and quality of the ambulation that is sufficient in the postoperative period. At present, patients on the surgical floor who are completely independent and without any devices (eg. Oxygen, nasogastric tubes, chest tubes) are freely able to ambulate at will although there is no reliable way to track this progress. Other patients with devices are limited to waiting for nursing or ancillary staff to assist them with securing the devices that they require in the postoperative period. Ambulation has been positively associated with decreased postoperative complications ranging from bowel function to deep venous thrombosis to pneumonia.https://jdc.jefferson.edu/patientsafetyposters/1065/thumbnail.jp

Photometry and spectroscopy of faint candidate spectrophotometric standard DA white dwarfs

We present precise photometry and spectroscopy for 23 candidate spectrophotometric standard white dwarfs. The selected stars are distributed in the Northern hemisphere and around the celestial equators and are all fainter than r ~ 16.5 mag. This network of stars, when established as standards, together with the three Hubble Space Telescope primary CALSPEC white dwarfs, will provide a set of spectrophotometric standards to directly calibrate data products to better than 1%. These new faint standard white dwarfs will have enough signal-to-noise ratio in future deep photometric surveys and facilities to be measured accurately while still avoiding saturation in such surveys. They will also fall within the dynamic range of large telescopes and their instruments for the foreseeable future. This paper discusses the provenance of the observational data for our candidate standard stars. The comparison with models, reconciliation with reddening, and the consequent derivation of the full spectral energy density distributions for each of them is reserved for a subsequent paper.Comment: 31 pages, 17 figures, 10 tables, ApJ in press (accepted on December 23rd, 2018

Integrated parameters of star clusters: A comparison of theory and observations

(Abridged) This paper presents integrated magnitude and colours for synthetic clusters. The integrated parameters have been obtained for the whole cluster population as well as for the main-sequence (MS) population of star clusters. We have also estimated observed integrated magnitudes and colours of MS population of galactic open clusters, LMC and SMC star clusters. It is found that the colour evolution of MS population of star clusters is not affected by the stochastic fluctuations, however these fluctuations significantly affect the colour evolution of the whole cluster population. The fluctuations are maximum in $(V-I)$ colour in the age range 6.7 $<$ log (age) $<$ 7.5. Evolution of integrated colours of MS population of the clusters in the Milky Way, LMC and SMC, obtained in the present study are well explained by the present synthetic cluster model. The observed integrated $(B-V)$ colours of MS population of LMC star clusters having age $\geq$ 500 Myr seem to be distributed around $Z=$ 0.004 model, whereas $(V-I)$ colours are found to be more bluer than those predicted by the $Z=$ 0.004 model. $(V-I)$ vs $(B-V)$ two-colour diagram for the MS population of the Milky Way star clusters shows a fair agreement between the observations and present model, however the diagrams for LMC and SMC clusters indicate that observed $(V-I)$ colours are relatively bluer. Possible reasons for this anomaly have been discussed.Comment: 35 pages, 20 figs, accepted for publication in MNRA

Segue 2: A Prototype of the Population of Satellites of Satellites

We announce the discovery of a new Milky Way satellite Segue 2 found in the data of the Sloan Extension for Galactic Understanding and Exploration (SEGUE). We followed this up with deeper imaging and spectroscopy on the Multiple Mirror Telescope. From this, we derive a luminosity of M_v = -2.5, a half-light radius of 34 pc and a systemic velocity of -40$ km/s. Our MMT data also provides evidence for a stream around Segue 2 at a similar heliocentric velocity, and the SEGUE data show that it is also present in neighboring fields. We resolve the velocity dispersion of Segue 2 as 3.4 km/s and the possible stream as about 7 km/s. This object shows points of comparison with other recent discoveries, Segue 1, Boo II and Coma. We speculate that all four objects may be representatives of a population of satellites of satellites -- survivors of accretion events that destroyed their larger but less dense parents. They are likely to have formed at redshifts z > 10 and are good candidates for fossils of the reionization epoch.Comment: MNRAS, Submitte

The Star Formation & Chemical Evolution History of the Fornax Dwarf Spheroidal Galaxy

We present deep photometry in the B,V and I filters from CTIO/MOSAIC for about 270.000 stars in the Fornax dwarf Spheroidal galaxy, out to a radius of r_ell\sim0.8 degrees. By combining the accurately calibrated photometry with the spectroscopic metallicity distributions of individual Red Giant Branch stars we obtain the detailed star formation and chemical evolution history of Fornax. Fornax is dominated by intermediate age (1-10 Gyr) stellar populations, but also includes ancient (10-14 Gyr), and young (<1 Gyr) stars. We show that Fornax displays a radial age gradient, with younger, more metal-rich populations dominating the central region. This confirms results from previous works. Within an elliptical radius of 0.8 degrees, or 1.9 kpc from the centre, a total mass in stars of 4.3x10^7 Msun was formed, from the earliest times until 250 Myr ago. Using the detailed star formation history, age estimates are determined for individual stars on the upper RGB, for which spectroscopic abundances are available, giving an age-metallicity relation of the Fornax dSph from individual stars. This shows that the average metallicity of Fornax went up rapidly from [Fe/H]<-2.5 dex to [Fe/H]=-1.5 dex between 8-12 Gyr ago, after which a more gradual enrichment resulted in a narrow, well-defined sequence which reaches [Fe/H]\sim-0.8 dex, \sim3 Gyr ago. These ages also allow us to measure the build-up of chemical elements as a function of time, and thus determine detailed timescales for the evolution of individual chemical elements. A rapid decrease in [Mg/Fe] is seen for the stars with [Fe/H]>-1.5 dex, with a clear trend in age.Comment: 18 pages, 20 figure

Chemical evolution of the Small Magellanic Cloud based on planetary nebulae

We investigate the chemical evolution of the Small Magellanic Cloud (SMC) based on abundance data of planetary nebulae (PNe). The main goal is to investigate the time evolution of the oxygen abundance in this galaxy by deriving an age-metallicity relation. Such a relation is of fundamental importance as an observational constraint of chemical evolution models of the SMC. We have used high quality PNe data in order to derive the properties of the progenitor stars, so that the stellar ages could be estimated. We collected a large number of measured spectral fluxes for each nebula, and derived accurate physical parameters and nebular abundances. New spectral data for a sample of SMC PNe obtained between 1999 and 2002 are also presented. These data are used together with data available in the literature to improve the accuracy of the fluxes for each spectral line. We obtained accurate chemical abundances for PNe in the Small Magellanic Cloud, which can be useful as tools in the study of the chemical evolution of this galaxy and of Local Group galaxies. We present the resulting oxygen versus age diagram and a similar relation involving the [Fe/H] metallicity based on a correlation with stellar data. We discuss the implications of the derived age-metallicity relation for the SMC formation, in particular by suggesting a star formation burst in the last 2-3 Gyr.Comment: 11 pages, 6 figures, accepted for publication in Astronomy and Astrophysic