X-Ray Grating Observations of Recurrent Nova T Pyxidis During The 2011 Outburst

The recurrent nova T Pyx was observed with the X-ray gratings of Chandra and XMM-Newton, 210 and 235 days, respectively, after the discovery of the 2011 April 14 outburst. The X-ray spectra show prominent emission lines of C, N, and O, with broadening corresponding to a full width at half maximum of ~2000-3000 km/s, and line ratios consistent with high-density plasma in collisional ionization equilibrium. On day 210 we also measured soft X-ray continuum emission that appears to be consistent with a white dwarf (WD) atmosphere at a temperature ~420,000 K, partially obscured by anisotropic, optically thick ejecta. The X-ray continuum emission is modulated with the photometric and spectroscopic period observed in quiescence. The continuum at day 235 indicated a WD atmosphere at a consistent effective temperature of 25 days earlier, but with a lower flux. The effective temperature indicates a mass of ~1 solar mass. The conclusion of partial WD obscuration is supported by the complex geometry of non-spherically-symmetric ejecta confirmed in recent optical spectra obtained with the Southern African Large Telescope (SALT) in November and December of 2012. These spectra exhibited prominent [O III] nebular lines with velocity structures typical of bipolar ejecta.Comment: Accepted to ApJ 2013 October 23, 14 pages, 9 figures, 3 table

The age-adjusted Charlson comorbidity index as a predictor of survival in surgically treated vulvar cancer patients

OBJECTIVE: To evaluate the impact of age-adjusted Charlson comorbidity index (ACCI) in predicting disease-free survival (DFS), overall survival (OS), and cancer-specific survival (CSS) among surgically treated patients with vulvar carcinoma. The secondary aim is to evaluate its impact as a predictor of the pattern of recurrence. METHODS: We retrospectively evaluated data of patients that underwent surgical treatment for vulvar cancer from 1998 to 2016. ACCI at the time of primary surgery was evaluated and patients were classified as low (ACCI 0-1), intermediate (ACCI 2-3), and high risk (>3). DFS, OS and CSS were analyzed using the Kaplan-Meir and the Cox proportional hazard models. Logistic regression model was used to assess predictors of distant and local recurrence. RESULTS: Seventy-eight patients were included in the study. Twelve were classified as low, 36 as intermediate, and 30 as high risk according to their ACCI. Using multivariate analysis, ACCI class was an independent predictor of worse DFS (hazard ratio [HR]=3.04; 95% confidence interval [CI]=1.54-5.99; p<0.001), OS (HR=5.25; 95% CI=1.63-16.89; p=0.005) and CSS (HR=3.79; 95% CI=1.13-12.78; p=0.03). Positive nodal status (odds ratio=8.46; 95% CI=2.13-33.58; p=0.002) was the only parameter correlated with distant recurrence at logistic regression. CONCLUSION: ACCI could be a useful tool in predicting prognosis in surgically treated vulvar cancer patients. Prospective multicenter trials assessing the role of ACCI in vulvar cancer patients are warranted

The influence of playing surface on the loading response to soccer-specific activity

Context: The influence of playing surface on injury risk in soccer is contentious, and 6 contemporary technologies permit an in-vivo assessment of mechanical loading on the 7 player. Objective: To quantify the influence of playing surface on the PlayerLoad elicited 8 during soccer-specific activity. Design: Repeated measures, field-based. Setting: 9 Regulation soccer pitches. Participants: 15 amateur soccer players (22.1 ± 2.4 yrs), injury 10 free with ≥ 6 yrs competitive experience. Interventions: Each player completed 11 randomised order trials of a soccer-specific field test on natural turf, astroturf and third 12 generation artificial turf. GPS units were located at C7 and the mid-tibia of each leg to 13 measure triaxial acceleration (100Hz). Main Outcome Measures: Total accumulated 14 PlayerLoad in each movement plane was calculated for each trial. Ratings of perceived 15 exertion (RPE) and visual analogue scales (VAS) assessing lower-limb muscle soreness 16 were measured as markers of fatigue. Results: ANOVA revealed no significant main 17 effect for playing surface on total PlayerLoad (P = 0.55), distance covered (P = 0.75), or 18 post-exercise measures of RPE (P = 0.98) and VAS (P = 0.61). There was a significant 19 main effect for GPS location (P < 0.001), with lower total loading elicited at C7 than mid20 tibia (P < 0.001), but with no difference between limbs (P = 0.70). There was no unit 21 placement x surface interaction (P = 0.98). There was also a significant main effect for 22 GPS location on the relative planar contributions to loading (P < 0.001). Relative planar 23 contributions to loading in the AP:ML:V planes was 25:27:48 at C7 and 34:32:34 at mid24 tibia. Conclusions: PlayerLoad metrics suggest that playing surface does not influence 25 mechanical loading during soccer-specific activity (not including tackling). Clinical 2 26 reasoning should consider that PlayerLoad magnitude and axial contributions were 27 sensitive to unit placement, highlighting opportunities in the objective monitoring of load 28 during rehabilitation

Testing current synthesis models of the X-ray background

We present synthesis models of the X-ray background where the available X-ray observational constraints are used to derive information on the AGN population properties. We show the need for luminous X-ray absorbed AGNs, the QSO2s, in reproducing the 2-10 keV source counts at relatively bright fluxes. We compare a model where the evolution of absorbed AGNs is faster than that of unabsorbed ones, with a standard model where absorbed and unabsorbed AGNs evolve at the same rate. It is found that an increase by a factor of ~2 from z=0 to z~1.3 in the ratio between absorbed and unabsorbed AGNs would provide a significant improvement in the data description. Finally, we make predictions on the AGNs to be observed in deep X-ray surveys which contain information on the AGN space density at high redshift.Comment: 11 pages with 8 figures, A&A accepte

The HELLAS2XMM Survey. XII. The infrared/sub-millimeter view of an X-ray selected Type 2 quasar at z=2

We present multi-wavelength observations (from optical to sub-millimeter, including Spitzer and SCUBA) of H2XMMJ 003357.2-120038 (also GD158_19), an X-ray selected, luminous narrow-line (Type 2) quasar at z=1.957 selected from the HELLAS2XMM survey. Its broad-band properties can be reasonably well modeled assuming three components: a stellar component to account for the optical and near-IR emission, an AGN component (i.e., dust heated by an accreting active nucleus), dominant in the mid-IR, with an optical depth at 9.7 micron along the line of sight (close to the equatorial plane of the obscuring matter) of tau(9.7)=1 and a full covering angle of the reprocessing matter (torus) of 140 degrees, and a far-IR starburst component (i.e., dust heated by star formation) to reproduce the wide bump observed longward of 70 micron. The derived star-formation rate is about 1500 solar masses per year. The overall modeling indicates that GD158_19 is a high-redshift X-ray luminous, obscured quasar with coeval powerful AGN activity and intense star formation. It is probably caught before the process of expelling the obscuring gas has started, thus quenching the star formation.Comment: 7 pages, 3 figures, 1 table, accepted for publication by MNRA

Text and Transmission

The modern reader may encounter the Greek text of Euripides' surviving plays in many forms: in print either in complete editions or in separate editions of single plays published with translations or commentaries or both, and in digital form at well-known sites on the internet. When Euripides composed his plays, he is most likely to have written on a papyrus roll, although for rough drafts of small sections he could have used wax tablets, loose papyrus sheets, or pottery sherds. Although the papyrus rolls and early codices give us intriguing glimpses of the text of the Euripides plays up the seventh century CE, the surviving complete plays depend on the medieval textual tradition. For Euripides as for Aeschylus and Sophocles, Alexandrian scholars collected texts of as many plays as they could, comparing their titles to those known from the didascalic records. About seventy plays of Euripides never reached the medieval manuscript tradition

Constraining dark energy with gamma-ray bursts

We use the measurement of gamma-ray burst (GRB) distances to constrain dark energy cosmological model parameters. We employ two methods for analyzing GRB data - fitting luminosity relation of GRBs in each cosmology and using distance measures computed from binned GRB data. Current GRB data alone cannot tightly constrain cosmological parameters and allow for a wide range of dark energy models.Comment: 27 pages, 12 figures, two methods of analysing GRB data, updated to match published version

Faint-end Quasar Luminosity Functions from Cosmological Hydrodynamic Simulations

We investigate the predictions for the faint-end quasar luminosity function (QLF) and its evolution using fully cosmological hydrodynamic simulations which self-consistently follow star formation, black hole growth and associated feedback processes. We find remarkably good agreement between predicted and observed faint end of the optical and X-ray QLFs (the bright end is not accessible in our simulated volumes) at z < 2. At higher redshifts our simulations tend to overestimate the QLF at the faintest luminosities. We show that although the low (high) luminosity ranges of the faint-end QLF are dominated by low (high) mass black holes, a wide range of black hole masses still contributes to any given luminosity range. This is consistent with the complex lightcurves of black holes resulting from the detailed hydrodynamics followed in the simulations. Consistent with the results on the QLFs, we find good agreement for the evolution of the comoving number density (in optical, soft and hard X-ray bands) of AGN for luminosities above 10^43 erg/s. However, the luminosity density evolution from the simulation appears to imply a peak at higher redshift than constrained from hard X-ray data (but not in optical). Our predicted excess at the faintest fluxes at z >= 2 does not lead to an overestimate to the total X-ray background and its contribution is at most a factor of two larger than the unresolved fraction of the 2-8 keV background. Even though this could be explained by some yet undetected, perhaps heavily obscured faint quasar population, we show that our predictions for the faint sources at high redshifts (which are dominated by the low mass black holes) in the simulations are likely affected by resolution effects.Comment: 12 pages, 9 figures; submitted and reviewed by MNRA