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Physician Attitudes Toward Homosexuality and HIV: The PATHH-III Survey.
PurposeThe aims of this study were (1) to evaluate current physician attitudes toward homosexuality and homosexual, transgender, and HIV-positive individuals and (2) to compare current attitudes of those from prior surveys of the same population, the San Diego County medical community.MethodsAn online survey was conducted during November-December 2017 to assess general attitudes toward homosexuality and medically focused items that addressed homosexual orientation, transgender identity, and HIV. Responses were weighted for nonresponse. Predictors of stigma were assessed using generalized linear models. Trends across three surveys of the same population in 1982, 1999, and 2017 using common items were assessed using unweighted responses.ResultsOf 4418 eligible physicians, 491 (11.1%) responded (median age 55 years, 38% female and 8.7% gay or bisexual). Regarding admission to medical school, 1% opposed admitting a homosexual applicant, 2% a transgender applicant, and 5% an HIV-positive applicant. Regarding consultative referral to a pediatrician, 3% would discontinue referral to a homosexual pediatrician, 5% to a transgender pediatrician, and 10% to an HIV-positive pediatrician. Regarding discomfort treating patients, 7% reported discomfort treating homosexual patients, 22% transgender patients, and 13% HIV-positive patients. Earlier year of graduation from medical school, male gender, and heterosexual orientation were significant predictors of stigma-associated responses. Compared with the results from surveys in 1982 and 1999, the current results suggest substantively less stigma associated with homosexuality and HIV.ConclusionThere have been substantive declines over a 35-year period in the prevalence of stigmatizing attitudes toward sexual minorities and HIV-positive people among physician respondents in three survey waves of the San Diego County medical community
Relative Sizes of X-ray and Optical Images of Elliptical Galaxies; Correlation with X-ray Luminosity
Optical parameters of elliptical galaxies are tightly correlated, but their
x-ray parameters vary widely. The x-ray luminosity L_x ranges over more than an
order of magnitude for ellipticals having similar optical luminosity L_B. The
source of this scatter has been elusive. We show here that the dispersion in
L_x for fixed optical luminosity L_B correlates strongly with the dimensionless
ratio of the sizes of the x-ray and optical images, r_ex/r_e. Specifically, we
find that (L_x/L_B) is proportional to (r_{ex}/r_e)^{0.60 \pm 0.30}, a version
of the correlation that is independent of distance. This correlation may be a
natural result of mergings and tidal truncations that are expected during the
formation and early evolution of ellipticals in groups of galaxies. The radial
structure of x-ray images also varies: some are compact (e.g. NGC 4649, 7626,
5044), others diffuse (e.g. NGC 4636, 1399).Comment: 5 pages, 3 figures. Accepted for publication in Astrophysical Journal
Letter
Spitzer Observations of Transient, Extended Dust in Two Elliptical Galaxies: New Evidence of Recent Feedback Energy Release in Galactic Cores
Spitzer observations of extended dust in two optically normal elliptical
galaxies provide a new confirmation of buoyant feedback outflow in the hot gas
atmospheres around these galaxies. AGN feedback energy is required to prevent
wholesale cooling and star formation in these group-centered galaxies. In NGC
5044 we observe interstellar (presumably PAH) emission at 8 microns out to
about 5 kpc. Both NGC 5044 and 4636 have extended 70 microns emission from cold
dust exceeding that expected from stellar mass loss. The sputtering lifetime of
this extended dust in the ~1keV interstellar gas, ~10^7 yrs, establishes the
time when the dust first entered the hot gas. Evidently the extended dust
originated in dusty disks or clouds, commonly observed in elliptical galaxy
cores, that were disrupted, heated and buoyantly transported outward. The
surviving central dust in NGC 5044 and 4636 has been disrupted into many small
filaments. It is remarkable that the asymmetrically extended 8 micron emission
in NGC 5044 is spatially coincident with Halpha+[NII] emission from warm gas. A
calculation shows that dust-assisted cooling in buoyant hot gas moving out from
the galactic core can cool within a few kpc in about ~10^7 yrs, explaining the
optical line emission observed. The X-ray images of both galaxies are
disturbed. All timescales for transient activity - restoration of equilibrium
and buoyant transport in the hot gas, dynamics of surviving dust fragments, and
dust sputtering - are consistent with a central release of feedback energy in
both galaxies about 10^7 yrs ago.Comment: 13 pages. Accepted by ApJ; minor typos correcte
Energetics of X-ray Cavities and Radio Lobes in Galaxy Clusters
We describe the formation and evolution of X-ray cavities in the hot gas of
galaxy clusters. The cavities are formed only with relativistic cosmic rays
that eventually diffuse into the surrounding gas. We explore the evolution of
cavities formed with a wide range of cosmic ray diffusion rates. In previous
numerical simulations cavities are formed by injecting ultra-hot but
non-relativistic gas which increases the global thermal energy, offsetting
radiative losses in the gas and helping to solve the cooling flow problem.
Contrary to these results, we find that X-ray cavities formed solely by cosmic
rays have a global cooling effect. As the cluster gas is displaced by cosmic
rays, a global expansion of the cluster gas occurs with associated cooling that
exceeds the heating by shock waves as the cavity forms. Most cosmic rays in our
cavity evolutions do not move beyond the cooling radius even after 1 Gyr. The
gas density is depressed by cosmic rays, becomes buoyant, and undergoes a
significant outward mass transfer within the cooling radius, carrying cosmic
rays and relatively low entropy gas to distant regions in the cluster where it
remains for times exceeding the local cooling time in the hot gas. This
post-cavity mass outflow due to cosmic ray buoyancy may contribute toward
solving the cooling flow problem. We describe the energetics, size, stability
and buoyant rise of X-ray cavities in detail, showing how each depends on the
rate of cosmic ray diffusion.Comment: 17 pages, 8 figures, accepted by Ap
Evolution of Hot Gas and Dark Halos in Group-Dominant Elliptical Galaxies: Influence of Cosmic Inflow
We study the complete dynamical evolution of hot interstellar gas in massive
elliptical galaxies born into a simple flat universe beginning with an
overdense perturbation. Within the turn-around radius dark matter flows in a
self-similar fashion into a stationary Navarro-Frenk-White halo and the
baryonic gas shocks. After a few gigayears, when enough gas accumulates within
the accretion shock, the de Vaucouleurs stellar system is constructed and the
energy from Type II supernovae is released. The stars and dark halo are matched
to NGC 4472. Gas continues to enter the galaxy by secondary infall and by
stellar mass loss based on a Salpeter IMF. After about 13 Gyrs the temperature
and density distribution in the hot gas agree quite well with the hot
interstellar gas observed in NGC 4472. As a result of supernova-driven outflow,
the present day baryonic fraction has a deep minimum in the outer galactic
halo. When relatively gas-rich, X-ray luminous models are spatially truncated
at early times, simulating tidal events that may have occurred during galaxy
group dynamics, the current locus of truncated models lies just along the
, X-ray size correlation among well-observed ellipticals, providing
another striking confirmation of our simple model of elliptical evolution.Comment: 16 pages in AASTEX LaTeX with 14 figures; accepted by Astrophysical
Journa
Predictive validity of a brief antiretroviral adherence index: Retrospective cohort analysis under conditions of repetitive administration
<p>Abstract</p> <p>Background</p> <p>Newer antiretroviral (ARV) agents have improved pharmacokinetics, potency, and tolerability and have enabled the design of regimens with improved virologic outcomes. Successful antiretroviral therapy is dependent on patient adherence. In previous research, we validated a subset of items from the ACTG adherence battery as prognostic of virologic suppression at 6 months and correlated with adherence estimates from the Medication Event Monitoring System (MEMS). The objective of the current study was to validate the longitudinal use of the Owen Clinic adherence index in analyses of time to initial virologic suppression and maintenance of suppression.</p> <p>Results</p> <p>278 patients (naïve n = 168, experienced n = 110) met inclusion criteria. Median [range] time on the first regimen during the study period was 286 (30 – 1221) days. 217 patients (78%) achieved an undetectable plasma viral load (pVL) at median 63 days. 8.3% (18/217) of patients experienced viral rebound (pVL > 400) after initial suppression. Adherence scores varied from 0 – 25 (mean 1.06, median 0). The lowest detectable adherence score cut point using this instrument was ≥ 5 for both initial suppression and maintenance of suppression. In the final Cox model of time to first undetectable pVL, controlling for prior treatment experience and baseline viral load, the adjusted hazard ratio for time updated adherence score was 0.36<sub>score ≥ 5 </sub>(95% CI: 0.19–0.69) [reference: <5]. In the final generalized estimating equations (GEE) logistic regression model the adjusted odds ratio for time-updated adherence score was 0.17<sub>score ≥ 5 </sub>(0.05–0.66) [reference: <5].</p> <p>Conclusion</p> <p>A brief, longitudinally administered self report adherence instrument predicted both initial virologic suppression and maintenance of suppression in patients using contemporary ARV regimens. The survey can be used for identification of sub-optimal adherence with subsequent appropriate intervention.</p
Retrieved Products from Simulated Hyperspectral Observations of a Hurricane
This research uses GCM derived products, with 1 km spatial resolution and sampled every 10 minutes, over a moving area following the track of a simulated severe Atlantic storm. Model products were aggregated over sounder footprints corresponding to 13 km in LEO, 2 km in LEO, and 5 km in GEO sampled every 72 minutes. We simulated radiances for instruments with AIRS-like spectral coverage, spectral resolution, and channel noise, using these aggregated products as the truth, and analyzed them using a slightly modified version of the operational AIRS Version-6 retrieval algorithm. Accuracy of retrievals obtained using simulated AIRS radiances with a 13 km footprint was similar to that obtained using real AIRS data. Spatial coverage and accuracy of retrievals are shown for all three sounding scenarios. The research demonstrates the potential significance of flying Advanced AIRS-like instruments on future LEO and GEO missions
Utility of clinical assessment, imaging, and cryptococcal antigen titer to predict AIDS-related complicated forms of cryptococcal meningitis
<p>Abstract</p> <p>Background</p> <p>This study aimed to evaluate the prevalence and predictors of AIDS-related complicated cryptococcal meningitis. The outcome was complicated cryptococcal meningitis: prolonged (≥ 14 days) altered mental status, persistent (≥ 14 days) focal neurologic findings, cerebrospinal fluid (CSF) shunt placement or death. Predictor variable operating characteristics were estimated using receiver operating characteristic curve (ROC) analysis. Multivariate analysis identified independent predictors of the outcome.</p> <p>Results</p> <p>From 1990-2009, 82 patients with first episode of cryptococcal meningitis were identified. Of these, 14 (17%) met criteria for complicated forms of cryptococcal meningitis (prolonged altered mental status 6, persistent focal neurologic findings 7, CSF surgical shunt placement 8, and death 5). Patients with complicated cryptococcal meningitis had higher frequency of baseline focal neurological findings, head computed tomography (CT) abnormalities, mean CSF opening pressure, and cryptococcal antigen (CRAG) titers in serum and CSF. ROC area of log<sub>2 </sub>serum and CSF CRAG titers to predict complicated forms of cryptococcal meningitis were comparable, 0.78 (95%CI: 0.66 to 0.90) vs. 0.78 (95% CI: 0.67 to 0.89), respectively (χ<sup>2</sup>, p = 0.95). The ROC areas to predict the outcomes were similar for CSF pressure and CSF CRAG titers. In a multiple logistic regression model, the following were significant predictors of the outcome: baseline focal neurologic findings, head CT abnormalities and log<sub>2 </sub>CSF CRAG titer.</p> <p>Conclusions</p> <p>During initial clinical evaluation, a focal neurologic exam, abnormal head CT and large cryptococcal burden measured by CRAG titer are associated with the outcome of complicated cryptococcal meningitis following 2 weeks from antifungal therapy initiation.</p
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