Haemorrhoidal artery ligation versus rubber band ligation for the management of symptomatic second-degree and third-degree haemorrhoids (HubBLe): a multicentre, open-label, randomised controlled trial.

BACKGROUND: Optimum surgical intervention for low-grade haemorrhoids is unknown. Haemorrhoidal artery ligation (HAL) has been proposed as an efficacious, safe therapy while rubber band ligation (RBL) is a commonly used outpatient treatment. We compared recurrence after HAL versus RBL in patients with grade II-III haemorrhoids. METHODS: This multicentre, open-label, parallel group, randomised controlled trial included patients from 17 acute UK NHS trusts. We screened patients aged 18 years or older presenting with grade II-III haemorrhoids. We excluded patients who had previously received any haemorrhoid surgery, more than one injection treatment for haemorrhoids, or more than one RBL procedure within 3 years before recruitment. Eligible patients were randomly assigned (in a 1:1 ratio) to either RBL or HAL with Doppler. Randomisation was computer-generated and stratified by centre with blocks of random sizes. Allocation concealment was achieved using a web-based system. The study was open-label with no masking of participants, clinicians, or research staff. The primary outcome was recurrence at 1 year, derived from the patient's self-reported assessment in combination with resource use from their general practitioner and hospital records. Recurrence was analysed in patients who had undergone one of the interventions and been followed up for at least 1 year. This study is registered with the ISRCTN registry, ISRCTN41394716. FINDINGS: From Sept 9, 2012, to May 6, 2014, of 969 patients screened, 185 were randomly assigned to the HAL group and 187 to the RBL group. Of these participants, 337 had primary outcome data (176 in the RBL group and 161 in the HAL group). At 1 year post-procedure, 87 (49%) of 176 patients in the RBL group and 48 (30%) of 161 patients in the HAL group had haemorrhoid recurrence (adjusted odds ratio [aOR] 2·23, 95% CI 1·42-3·51; p=0·0005). The main reason for this difference was the number of extra procedures required to achieve improvement (57 [32%] participants in the RBL group and 23 [14%] participants in the HAL group had a subsequent procedure for haemorrhoids). The mean pain 1 day after procedure was 3·4 (SD 2·8) in the RBL group and 4·6 (2·8) in the HAL group (difference -1·2, 95% CI -1·8 to -0·5; p=0·0002); at day 7 the scores were 1·6 (2·3) in the RBL group and 3·1 (2·4) in the HAL group (difference -1·5, -2·0 to -1·0; p<0·0001). Pain scores did not differ between groups at 21 days and 6 weeks. 15 individuals reported serious adverse events requiring hospital admission. One patient in the RBL group had a pre-existing rectal tumour. Of the remaining 14 serious adverse events, 12 (7%) were among participants treated with HAL and two (1%) were in those treated with RBL. Six patients had pain (one treated with RBL, five treated with HAL), three had bleeding not requiring transfusion (one treated with RBL, two treated with HAL), two in the HAL group had urinary retention, two in the HAL group had vasovagal upset, and one in the HAL group had possible sepsis (treated with antibiotics). INTERPRETATION: Although recurrence after HAL was lower than a single RBL, HAL was more painful than RBL. The difference in recurrence was due to the need for repeat bandings in the RBL group. Patients (and health commissioners) might prefer such a course of RBL to the more invasive HAL. FUNDING: NIHR Health Technology Assessment programme

Early Radio and X-Ray Observations of the Youngest Nearby Type Ia Supernova PTF 11kly (SN 2011fe)

On 2011 August 24 (UT) the Palomar Transient Factory (PTF) discovered PTF11kly (SN 2011fe), the youngest and most nearby Type Ia supernova (SN Ia) in decades. We followed this event up in the radio (centimeter and millimeter bands) and X-ray bands, starting about a day after the estimated explosion time.We present our analysis of the radio and X-ray observations, yielding the tightest constraints yet placed on the pre-explosion mass-loss rate from the progenitor system of this supernova. We find a robust limit of Ṁ ≾ 10^(−8)(w/100 km s^(−1))M_☉ yr^(−1) from sensitive X-ray non-detections, as well as a similar limit from radio data, which depends, however, on assumptions about microphysical parameters. We discuss our results in the context of single-degenerate models for SNe Ia and find that our observations modestly disfavor symbiotic progenitor models involving a red giant donor, but cannot constrain systems accreting from main-sequence or sub-giant stars, including the popular supersoft channel. In view of the proximity of PTF11kly and the sensitivity of our prompt observations, we would have to wait for a long time (a decade or longer) in order to more meaningfully probe the circumstellar matter of SNe Ia

Ultraviolet Light Curves of Supernovae with Swift Uvot

We present ultravioliet (UV) observations of supernovae (SNe) obtained with the UltraViolet/Optical Telescope (UVOT) on board the Swift spacecraft. This is the largest sample of UV light curves from any single instrument and covers all major SN types and most subtypes. The UV light curves of SNe Ia are fairly homogenous while SNe Ib/c and IIP show more variety in their light curve shapes. The UV-optical colors clearly differentiate SNe Ia and IIP, particularly at early times. The color evolution of SNe IIP, however, makes their colors similar to SNe Ia at about 20 days after explosion. SNe Ib/c are shown to have varied UV-optical colors. The use of UV colors to help type SNe will be important for high redshift SNe discovered in optical observations. These data can be added to ground based optical and near infrared data to create bolometric light curves of individual objects and as checks on generic bolometric corrections used in the absence of UV data. This sample can also be compared with rest-frame UV observations of high redshift SNe observed at optical wavelengths.Comment: 11 pages, including 8 figures. Submitted to A

Real-Time Detection and Rapid Multiwavelength Follow-up Observations of a Highly Subluminous Type II-P Supernova from the Palomar Transient Factory Survey

The Palomar Transient Factory (PTF) is an optical wide-field variability survey carried out using a camera with a 7.8 square degree field of view mounted on the 48-in Oschin Schmidt telescope at Palomar Observatory. One of the key goals of this survey is to conduct high-cadence monitoring of the sky in order to detect optical transient sources shortly after they occur. Here, we describe the real-time capabilities of the PTF and our related rapid multiwavelength follow-up programs, extending from the radio to the gamma-ray bands. We present as a case study observations of the optical transient PTF10vdl (SN 2010id), revealed to be a very young core-collapse (Type II-P) supernova having a remarkably low luminosity. Our results demonstrate that the PTF now provides for optical transients the real-time discovery and rapid-response follow-up capabilities previously reserved only for high-energy transients like gamma-ray bursts.Comment: ApJ, in press; all spectroscopic data available from the Weizmann Institute of Science Experimental Astrophysics Spectroscopy System (WISEASS; http://www.weizmann.ac.il/astrophysics/wiseass/

Strong Ultraviolet Pulse From a Newborn Type Ia Supernova

Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious, One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations of strong but declining ultraviolet emission from a Type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some Type Ia supernovae arise from the single degenerate channel.Comment: Accepted for publication on the 21 May 2015 issue of Natur

PTF10fqs: A Luminous Red Nova in the Spiral Galaxy Messier 99

The Palomar Transient Factory (PTF) is systematically charting the optical transient and variable sky. A primary science driver of PTF is building a complete inventory of transients in the local Universe (distance less than 200 Mpc). Here, we report the discovery of PTF10fqs, a transient in the luminosity "gap" between novae and supernovae. Located on a spiral arm of Messier 99, PTF 10fqs has a peak luminosity of Mr = -12.3, red color (g-r = 1.0) and is slowly evolving (decayed by 1 mag in 68 days). It has a spectrum dominated by intermediate-width H (930 km/s) and narrow calcium emission lines. The explosion signature (the light curve and spectra) is overall similar to thatof M85OT2006-1, SN2008S, and NGC300OT. The origin of these events is shrouded in mystery and controversy (and in some cases, in dust). PTF10fqs shows some evidence of a broad feature (around 8600A) that may suggest very large velocities (10,000 km/s) in this explosion. Ongoing surveys can be expected to find a few such events per year. Sensitive spectroscopy, infrared monitoring and statistics (e.g. disk versus bulge) will eventually make it possible for astronomers to unravel the nature of these mysterious explosions.Comment: 12 pages, 12 figures, Replaced with published versio

Rapidly Decaying Supernova 2010X: A Candidate ".Ia" Explosion

We present the discovery, photometric and spectroscopic follow-up observations of SN 2010X (PTF 10bhp). This supernova decays exponentially with tau_d=5 days, and rivals the current recordholder in speed, SN 2002bj. SN 2010X peaks at M_r=-17mag and has mean velocities of 10,000 km/s. Our light curve modeling suggests a radioactivity powered event and an ejecta mass of 0.16 Msun. If powered by Nickel, we show that the Nickel mass must be very small (0.02 Msun) and that the supernova quickly becomes optically thin to gamma-rays. Our spectral modeling suggests that SN 2010X and SN 2002bj have similar chemical compositions and that one of Aluminum or Helium is present. If Aluminum is present, we speculate that this may be an accretion induced collapse of an O-Ne-Mg white dwarf. If Helium is present, all observables of SN 2010X are consistent with being a thermonuclear Helium shell detonation on a white dwarf, a ".Ia" explosion. With the 1-day dynamic-cadence experiment on the Palomar Transient Factory, we expect to annually discover a few such events.Comment: 6 pages, 5 figures; Minor Changes; Note correction in Fig 4 caption; published by ApJ

The Role of Type Ia Supernovae in Chemical Evolution I: Lifetime of Type Ia Supernovae and Galactic Supernova Rates

We construct a new model of Type Ia Supernovae (SNe Ia), based on the single degenerate scenario, taking account of the metallicity dependences of the white dwarf (WD) wind and the mass-stripping effect on the binary companion star. Our model naturally predicts that the SN Ia lifetime distribution spans a range of 0.1-20 Gyr with the double peaks at ~0.1 and 1 Gyr. While the present SN Ia rate in elliptical galaxies can be reproduced with the old population of the red-giants+WD systems, the large SN Ia rate in radio galaxies could be explained with the young population of the main-sequence+WD systems. Because of the metallicity effect, i.e., because of the lack of winds from WDs in the binary systems, the SN Ia rate in the systems with [Fe/H]<-1, e.g., high-z spiral galaxies, is supposed to be very small. Our SN Ia model can give better reproduction of the [(alpha, Mn, Zn)/Fe]-[Fe/H] relations in the solar neighborhood than other models such as the double-degenerate scenario. The metallicity effect is more strongly required in the presence of the young population of SNe Ia. We also succeed in reproducing the galactic supernova rates with their dependence on the morphological type of galaxies, and the cosmic SN Ia rate history with a peak at z~1. At z>1, the predicted SN Ia rate decreases toward higher redshifts and SNe Ia will be observed only in the systems that have evolved with a short timescale of chemical enrichment. This suggests that the evolution effect in the supernova cosmology can be small.Comment: 56 pages, 20 figures, accepted to Ap

Near-Ultraviolet Properties of a Large Sample of Type Ia Supernovae as Observed with the Swift UVOT

We present ultraviolet (UV) and optical photometry of 26 Type Ia supernovae (SNe~Ia) observed from March 2005 to March 2008 with the NASA {\it Swift} Ultraviolet and Optical Telescope (UVOT). The dataset consists of 2133 individual observations, making it by far the most complete study of the UV emission from SNe~Ia to date. Grouping the SNe into three subclasses as derived from optical observations, we investigate the evolution of the colors of these SNe, finding a high degree of homogeneity within the normal subclass, but dramatic differences between that group and the subluminous and SN 2002cx-like groups. For the normal events, the redder UV filters on UVOT ($u$, $uvw1$) show more homogeneity than do the bluer UV filters ($uvm2$, $uvw2$). Searching for purely UV characteristics to determine existing optically based groupings, we find the peak width to be a poor discriminant, but we do see a variation in the time delay between peak emission and the late, flat phase of the light curves. The UV light curves peak a few days before the $B$ band for most subclasses (as was previously reported by Jha et al. 2006a), although the SN 2002cx-like objects peak at a very early epoch in the UV. That group also features the bluest emission observed among SNe~Ia. As the observational campaign is ongoing, we discuss the critical times to observe, as determined by this study, in order to maximize the scientific output of future observations.Comment: Accepted to Astrophysical Journa