We present continued radio observations of the tidal disruption event Swift J164449.3+573451 extending to delta t approx = 216 days after discovery. The data were obtained with the EVLA, AMI Large ...Array, CARMA, the SMA, and the VLBA+Effelsberg as part of a long-term program to monitor the expansion and energy scale of the relativistic outflow, and to trace the parsec-scale environment around a previously dormant supermassive black hole (SMBH). The new observations reveal a significant change in the radio evolution starting at delta t approx = 1 month, with a brightening at all frequencies that requires an increase in the energy by about an order of magnitude, and an overall density profile around the SMBH of rho is proportional tor super(-3/2) (0.1-1.2 pc) with a significant flattening at r approx = 0.4-0.6 pc. The increase in energy cannot be explained with continuous injection from an L is proportional tot super(-5/3) tail, which is observed in the X-rays. Instead, we conclude that the relativistic jet was launched with a wide range of Lorentz factors, obeying E(> Gammaj)is proportional toGamma super(-2.5)j. The similar ratios of duration to dynamical timescale for Sw 1644+57 and gamma-ray bursts (GRBs) suggest that this result may be applicable to GRB jets as well. The radial density profile may be indicative of Bondi accretion, with the inferred flattening at r ~ 0.5 pc in good agreement with the Bondi radius for a ~few x 10 super(6) M black hole. The density at ~0.5 pc is about a factor of 30 times lower than inferred for the Milky Way Galactic Center, potentially due to a smaller number of mass-shedding massive stars. From our latest observations ( delta t approx = 216 days) we find that the jet energy is E sub(j, iso) approx = 5 x 10 super(53) erg (E sub(j) approx = 2.4 x 10 super(51) erg or thetaj = 0.1), the radius is r approx = 1.2 pc, the Lorentz factor is Gammaj approx = 2.2, the ambient density is n approx = 0.2 cm super(-3), and the projected angular size is r sub(proj) approx = 25 mu as, below the resolution of the VLBA+Effelsberg. Assuming no future changes in the observed evolution and a final integrated total energy of E sub(j) approx = 10 super(52) erg, we predict that the radio emission from Sw 1644+57 should be detectable with the EVLA for several decades and will be resolvable with very long baseline interferometry in a few years.
A search for millicharged particles, a simple extension of the standard model, has been performed with the ArgoNeuT detector exposed to the Neutrinos at the Main Injector beam at Fermilab. The ...ArgoNeuT liquid argon time projection chamber detector enables a search for millicharged particles through the detection of visible electron recoils. We search for an event signature with two soft hits (MeV-scale energy depositions) aligned with the upstream target. For an exposure of the detector of 1.0×10^{20} protons on target, one candidate event has been observed, compatible with the expected background. This search is sensitive to millicharged particles with charges between 10^{-3}e and 10^{-1}e and with masses in the range from 0.1 to 3 GeV. This measurement provides leading constraints on millicharged particles in this large unexplored parameter space region.
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CMK, CTK, FMFMET, NUK, UL
To evaluate the image quality produced by six different iterative reconstruction (IR) algorithms in four CT systems in the setting of brain CT, using different radiation dose levels and iterative ...image optimisation levels.
An image quality phantom, supplied with a bone mimicking annulus, was examined using four CT systems from different vendors and four radiation dose levels. Acquisitions were reconstructed using conventional filtered back-projection (FBP), three levels of statistical IR and, when available, a model-based IR algorithm. The evaluated image quality parameters were CT numbers, uniformity, noise, noise-power spectra, low-contrast resolution and spatial resolution.
Compared with FBP, noise reduction was achieved by all six IR algorithms at all radiation dose levels, with further improvement seen at higher IR levels. Noise-power spectra revealed changes in noise distribution relative to the FBP for most statistical IR algorithms, especially the two model-based IR algorithms. Compared with FBP, variable degrees of improvements were seen in both objective and subjective low-contrast resolutions for all IR algorithms. Spatial resolution was improved with both model-based IR algorithms and one of the statistical IR algorithms.
The four statistical IR algorithms evaluated in the study all improved the general image quality compared with FBP, with improvement seen for most or all evaluated quality criteria. Further improvement was achieved with one of the model-based IR algorithms.
The six evaluated IR algorithms all improve the image quality in brain CT but show different strengths and weaknesses.
We present detailed optical photometry for 25 Type Ibc supernovae (SNe Ibc) within d 150 Mpc obtained with the robotic Palomar 60 inch telescope in 2004-2007. This study represents the first uniform, ...systematic, and statistical sample of multi-band SNe Ibc light curves available to date. We correct the light curves for host galaxy extinction using a new technique based on the photometric color evolution, namely, we show that the (V -- R) color of extinction-corrected SNe Ibc at Delta *Dt 10 days after V-band maximum is tightly distributed, (V -- R) V10 = 0.26 ? 0.06 mag. Using this technique, we find that SNe Ibc typically suffer from significant host galaxy extinction, E(B -- V) 0.4 mag. A comparison of the extinction-corrected light curves for helium-rich (Type Ib) and helium-poor (Type Ic) SNe reveals that they are statistically indistinguishable, both in luminosity and decline rate. We report peak absolute magnitudes of MR = --17.9 ? 0.9 mag and MR = --18.3 ? 0.6 mag for SNe Ib and Ic, respectively. Focusing on the broad-lined (BL) SNe Ic, we find that they are more luminous than the normal SNe Ibc sample, MR = --19.0 ? 1.1 mag, with a probability of only 1.6% that they are drawn from the same population of explosions. By comparing the peak absolute magnitudes of SNe Ic-BL with those inferred for local engine-driven explosions (GRB-SN 1998bw, XRF-SN 2006aj, and SN 2009bb) we find a 25% probability that relativistic SNe are drawn from the overall SNe Ic-BL population. Finally, we fit analytic models to the light curves to derive typical 56Ni masses of M Ni 0.2 and 0.5 M for SNe Ibc and SNe Ic-BL, respectively. With reasonable assumptions for the photospheric velocities, we further extract kinetic energy and ejecta mass values of M ej 2 M and EK 1051 erg for SNe Ibc, while for SNe Ic-BL we find higher values, M ej 5 M and EK 1052 erg. We discuss the implications for the progenitors of SNe Ibc and their relation to those of engine-driven explosions.
Objective
To evaluate how hysterectomy affects the prescription of analgesic, psychotropic and neuroactive drugs in women with endometriosis using population‐based nationwide registers.
Design
...Nationwide cohort study.
Setting
Swedish national registers, from 1 January 2009 to 31 December 2018.
Population
Women with benign disease undergoing a total hysterectomy during the 4‐year period of 2012–2015. Women with endometriosis (n = 1074) were identified and compared with women who did not have endometriosis (n = 10 890).
Methods
Prospectively collected data from two population‐based registers were linked: the Swedish National Quality Register of Gynaecological Surgery and the Swedish National Drug Register. Multivariate logistic regression was used as the main statistical method.
Main outcome measures
Changes in drug prescription over time for 3 years prior to and 3 years after hysterectomy.
Results
The frequency of prescription of analgesics was higher in women with endometriosis compared with women without endometriosis (OR 2.2, 95% CI 1.7–2.9). Among women with endometriosis, the prescription of analgesics (OR 1.0, 95% CI 0.8–1.2) did not decrease 3 years after hysterectomy compared with the 3 years prior to surgery. There was also a significantly higher rate of prescription of psychoactive (OR 1.6, 95% CI 1.4–2.0) and neuroactive drugs (OR 1.9, 95% CI 1.3–2.7) in the long term postoperatively.
Conclusions
In women undergoing hysterectomy, endometriosis was associated with a higher prescription rate of analgesics. In the endometriosis group the prescription of analgesic, psychoactive and neuroactive drugs did not decrease when comparing prescription rates for the 3 years prior to and the 3 years after surgery.
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In women with endometriosis, the long‐term prescription of analgesics did not decrease after hysterectomy.
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In women with endometriosis, the long‐term prescription of analgesics did not decrease after hysterectomy.
We present continued multi-frequency radio observations of the relativistic tidal disruption event Swift J164449.3+573451 extending to t approximate 600 days. The data were obtained with the JVLA and ...AMI Large Array as part of our on-going study of the jet energetics and the density structure of the parsec-scale environment around the disrupting super-massive black hole. We combine these data with public Swift/XRT and Chandra X-ray observations over the same time-frame to show that the jet has undergone a dramatic transition starting at approximate 500 days, with a sharp decline in the X-ray flux by about a factor of 170 on a timescale of delta t/t < or = 0.2. On the other hand, our radio data uniquely demonstrate that the low X-ray flux measured by Chandra at approximate 610 days is consistent with emission from the forward shock. Projecting forward, we predict that the emission in the radio and X-ray bands will evolve in tandem with similar decline rates.
Neoadjuvant chemotherapy (NACT) for early breast cancer can make breast-conserving surgery more feasible and might be more likely to eradicate micrometastatic disease than might the same chemotherapy ...given after surgery. We investigated the long-term benefits and risks of NACT and the influence of tumour characteristics on outcome with a collaborative meta-analysis of individual patient data from relevant randomised trials.
We obtained information about prerandomisation tumour characteristics, clinical tumour response, surgery, recurrence, and mortality for 4756 women in ten randomised trials in early breast cancer that began before 2005 and compared NACT with the same chemotherapy given postoperatively. Primary outcomes were tumour response, extent of local therapy, local and distant recurrence, breast cancer death, and overall mortality. Analyses by intention-to-treat used standard regression (for response and frequency of breast-conserving therapy) and log-rank methods (for recurrence and mortality).
Patients entered the trials from 1983 to 2002 and median follow-up was 9 years (IQR 5–14), with the last follow-up in 2013. Most chemotherapy was anthracycline based (3838 81% of 4756 women). More than two thirds (1349 69% of 1947) of women allocated NACT had a complete or partial clinical response. Patients allocated NACT had an increased frequency of breast-conserving therapy (1504 65% of 2320 treated with NACT vs 1135 49% of 2318 treated with adjuvant chemotherapy). NACT was associated with more frequent local recurrence than was adjuvant chemotherapy: the 15 year local recurrence was 21·4% for NACT versus 15·9% for adjuvant chemotherapy (5·5% increase 95% CI 2·4–8·6; rate ratio 1·37 95% CI 1·17–1·61; p=0·0001). No significant difference between NACT and adjuvant chemotherapy was noted for distant recurrence (15 year risk 38·2% for NACT vs 38·0% for adjuvant chemotherapy; rate ratio 1·02 95% CI 0·92–1·14; p=0·66), breast cancer mortality (34·4% vs 33·7%; 1·06 0·95–1·18; p=0·31), or death from any cause (40·9% vs 41·2%; 1·04 0·94–1·15; p=0·45).
Tumours downsized by NACT might have higher local recurrence after breast-conserving therapy than might tumours of the same dimensions in women who have not received NACT. Strategies to mitigate the increased local recurrence after breast-conserving therapy in tumours downsized by NACT should be considered—eg, careful tumour localisation, detailed pathological assessment, and appropriate radiotherapy.
Cancer Research UK, British Heart Foundation, UK Medical Research Council, and UK Department of Health.
Deep, late-time X-ray observations of the relativistic, engine-driven, type Ic SN 2012ap allow us to probe the nearby environment of the explosion and reveal the unique properties of relativistic ...supernova explosions (SNe). We find that on a local scale of ~0.01 pc the environment was shaped directly by the evolution of the progenitor star with a pre-explosion mass-loss rate of M < 5 x 10 super(-6) M sub(middot in circle) yr super(-1), in line with gamma-ray bursts (GRBs) and the other relativistic SN 2009bb. Like sub-energetic GRBs, SN 2012ap is characterized by a bright radio emission and evidence for mildly relativistic ejecta. However, its late-time ( delta t asymptotically = 20 days) X-ray emission is ~100 times fainter than the faintest sub-energetic GRB at the same epoch, with no evidence for late-time central engine activity. These results support theoretical proposals that link relativistic SNe like 2009bb and 2012ap with the weakest observed engine-driven explosions, where the jet barely fails to break out. Furthermore, our observations demonstrate that the difference between relativistic SNe and sub-energetic GRBs is intrinsic and not due to line-of-sight effects. This phenomenology can either be due to an intrinsically shorter-lived engine or to a more extended progenitor in relativistic SNe.
We present late-time radio observations of 68 local Type Ibc supernovae, including six events with broad optical absorption lines ("hypernovae"). None of these objects exhibit radio emission ...attributable to off-axis gamma-ray burst jets spreading into our line of sight. Comparison with our afterglow models reveals the following conclusions. (1) Less than 610% of Type Ibc supernovae are associated with typical gamma-ray bursts initially directed away from our line of sight; this places an empirical constraint on the GRB beaming factor of < fb super(-1) > 10 super(4), corresponding to an average jet opening angle,f sub(j) 0 8. (2) This holds in particular for the broad-lined supernovae (SNe 1997dq, 1997ef, 1998ey, 2002ap, 2002bl, and 2003jd), which have been argued to host GRB jets. Our observations reveal no evidence for typical (or even subenergetic) GRBs and rule out the scenario in which every broad-lined SN harbors a GRB at the 84% confidence level. Their large photospheric velocities and asymmetric ejecta (inferred from spectropolarimetry and nebular spectroscopy) appear to be characteristic of the nonrelativistic SN explosion and do not necessarily imply the existence of associated GRB jets.
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