A methodological framework is proposed for participatory scenario development on the basis of evidence from the literature, and is tested and refined through the development of scenarios for the ...future of UK uplands. The paper uses a review of previous work to justify a framework based around the following steps: i) define context and establish whether there is a basis for stakeholder engagement in scenario development; ii) systematically identify and represent relevant stakeholders in the process; iii) define clear objectives for scenario development with stakeholders including spatial and temporal boundaries; iv) select relevant participatory methods for scenario development, during initial scenario construction, evaluation and to support decision-making based on scenarios; and v) integrate local and scientific knowledge throughout the process. The application of this framework in case study research suggests that participatory scenario development has the potential to: i) make scenarios more relevant to stakeholder needs and priorities; ii) extend the range of scenarios developed; iii) develop more detailed and precise scenarios through the integration of local and scientific knowledge; and iv) move beyond scenario development to facilitate adaptation to future change. It is argued that participatory scenario development can empower stakeholders and lead to more consistent and robust scenarios that can help people prepare more effectively for future change.
•A methodological framework is proposed develop scenarios with stakeholders that can inform decision-making.•This has the potential to empower stakeholders and make scenarios more relevant to their needs.•Integrating local and scientific knowledge can increase the diversity, detail and precision of scenarios.•In this way, more consistent and robust scenarios can be developed to help people prepare more effectively for future change.
We present ultraviolet, optical and near-infrared data of the Type Ibn supernovae (SNe) 2010al and 2011hw. SN 2010al reaches an absolute magnitude at peak of M
R
= −18.86 ± 0.21. Its early light ...curve shows similarities with normal SNe Ib, with a rise to maximum slower than most SNe Ibn. The spectra are dominated by a blue continuum at early stages, with narrow P-Cygni He i lines indicating the presence of a slow-moving, He-rich circumstellar medium. At later epochs, the spectra well match those of the prototypical SN Ibn 2006jc, although the broader lines suggest that a significant amount of He was still present in the stellar envelope at the time of the explosion. SN 2011hw is somewhat different. It was discovered after the first maximum, but the light curve shows a double peak. The absolute magnitude at discovery is similar to that of the second peak (M
R
= −18.59 ± 0.25), and slightly fainter than the average of SNe Ibn. Though the spectra of SN 2011hw are similar to those of SN 2006jc, coronal lines and narrow Balmer lines are clearly detected. This indicates substantial interaction of the SN ejecta with He-rich, but not H-free, circumstellar material. The spectra of SN 2011hw suggest that it is a transitional SN Ibn/IIn event similar to SN 2005la. While for SN 2010al the spectrophotometric evolution favours a H-deprived Wolf–Rayet progenitor (of WN-type), we agree with the conclusion of Smith et al. that the precursor of SN 2011hw was likely in transition from a luminous blue variable to an early Wolf–Rayet (Ofpe/WN9) stage.
We present extensive datasets for a class of intermediate-luminosity optical transients known as luminous red novae. They show double-peaked light curves, with an initial rapid luminosity rise to a ...blue peak (at −13 to −15 mag), which is followed by a longer-duration red peak that sometimes is attenuated, resembling a plateau. The progenitors of three of them (NGC 4490−2011OT1, M 101−2015OT1, and SNhunt248), likely relatively massive blue to yellow stars, were also observed in a pre-eruptive stage when their luminosity was slowly increasing. Early spectra obtained during the first peak show a blue continuum with superposed prominent narrow Balmer lines, with P Cygni profiles. Lines of Fe II are also clearly observed, mostly in emission. During the second peak, the spectral continuum becomes much redder, Hα is barely detected, and a forest of narrow metal lines is observed in absorption. Very late-time spectra (∼6 months after blue peak) show an extremely red spectral continuum, peaking in the infrared (IR) domain. Hα is detected in pure emission at such late phases, along with broad absorption bands due to molecular overtones (such as TiO, VO). We discuss a few alternative scenarios for luminous red novae. Although major instabilities of single massive stars cannot be definitely ruled out, we favour a common envelope ejection in a close binary system, with possibly a final coalescence of the two stars. The similarity between luminous red novae and the outburst observed a few months before the explosion of the Type IIn SN 2011ht is also discussed.
Abstract Objective To determine the incidence and risk factors for endocarditis and reintervention in patients undergoing placement of right ventricle-to-pulmonary artery valve conduits. Methods All ...right ventricle–to–pulmonary artery valved conduits placed between 1995 and 2014 were included. Freedom from endocarditis, reintervention, and replacement were analyzed using the Kaplan-Meier method and parametric survival regression models. Results A total of 586 patients underwent placement of a total of 792 valved conduits, including 289 (36%) pulmonary homografts, 121 (15%) aortic homografts, 245 (31%) bovine jugular grafts, and 137 (17%) porcine heterografts. There were 474 (60%) primary placements and 318 (40%) replacements. The median duration of conduit follow-up was 7 years; 23 conduits developed endocarditis at a median of 5 years after surgery. The use of bovine jugular grafts was the sole significant risk factor associated with endocarditis (hazard ratio, 9.05; 95% confidence interval, 2.6–31.8 compared with homografts). The hazard was greater for bovine jugular grafts compared with the other conduit types and increased with time; however, bovine jugular grafts were associated with a lower risk for reintervention ( P < .0001) and replacement ( P = .0002). Factors associated with greater risk of both reintervention and replacement were younger age and smaller conduit size. In addition, a diagnosis of truncus arteriosus was associated with a greater risk for replacement ( P = .03). Conclusions Bovine jugular grafts are associated with a significantly greater risk of late endocarditis but with lower reintervention rates compared with other valved conduits. The risk of endocarditis and durability must be balanced during conduit selection. Antibiotic prophylaxis and a high index of suspicion for endocarditis are warranted in patients with bovine jugular grafts.
Complete surgical removal of the prostate, radical prostatectomy, is the most frequently used treatment option for men with localised prostate cancer. The use of laparoscopic (keyhole) and ...robot-assisted surgery has improved operative safety but the comparative effectiveness and cost-effectiveness of these options remains uncertain.
This study aimed to determine the relative clinical effectiveness and cost-effectiveness of robotic radical prostatectomy compared with laparoscopic radical prostatectomy in the treatment of localised prostate cancer within the UK NHS.
MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, BIOSIS, Science Citation Index and Cochrane Central Register of Controlled Trials were searched from January 1995 until October 2010 for primary studies. Conference abstracts from meetings of the European, American and British Urological Associations were also searched. Costs were obtained from NHS sources and the manufacturer of the robotic system. Economic model parameters and distributions not obtained in the systematic review were derived from other literature sources and an advisory expert panel.
Evidence was considered from randomised controlled trials (RCTs) and non-randomised comparative studies of men with clinically localised prostate cancer (cT1 or cT2); outcome measures included adverse events, cancer related, functional, patient driven and descriptors of care. Two reviewers abstracted data and assessed the risk of bias of the included studies. For meta-analyses, a Bayesian indirect mixed-treatment comparison was used. Cost-effectiveness was assessed using a discrete-event simulation model.
The searches identified 2722 potentially relevant titles and abstracts, from which 914 reports were selected for full-text eligibility screening. Of these, data were included from 19,064 patients across one RCT and 57 non-randomised comparative studies, with very few studies considered at low risk of bias. The results of this study, although associated with some uncertainty, demonstrated that the outcomes were generally better for robotic than for laparoscopic surgery for major adverse events such as blood transfusion and organ injury rates and for rate of failure to remove the cancer (positive margin) (odds ratio 0.69; 95% credible interval 0.51 to 0.96; probability outcome favours robotic prostatectomy = 0.987). The predicted probability of a positive margin was 17.6% following robotic prostatectomy compared with 23.6% for laparoscopic prostatectomy. Restriction of the meta-analysis to studies at low risk of bias did not change the direction of effect but did decrease the precision of the effect size. There was no evidence of differences in cancer-related, patient-driven or dysfunction outcomes. The results of the economic evaluation suggested that when the difference in positive margins is equivalent to the estimates in the meta-analysis of all included studies, robotic radical prostatectomy was on average associated with an incremental cost per quality-adjusted life-year that is less than threshold values typically adopted by the NHS (£30,000) and becomes further reduced when the surgical capacity is high.
The main limitations were the quantity and quality of the data available on cancer-related outcomes and dysfunction.
This study demonstrated that robotic prostatectomy had lower perioperative morbidity and a reduced risk of a positive surgical margin compared with laparoscopic prostatectomy although there was considerable uncertainty. Robotic prostatectomy will always be more costly to the NHS because of the fixed capital and maintenance charges for the robotic system. Our modelling showed that this excess cost can be reduced if capital costs of equipment are minimised and by maintaining a high case volume for each robotic system of at least 100-150 procedures per year. This finding was primarily driven by a difference in positive margin rate. There is a need for further research to establish how positive margin rates impact on long-term outcomes.
The National Institute for Health Research Health Technology Assessment programme.
Gravitational waves were discovered with the detection of binary black-hole mergers and they should also be detectable from lower-mass neutron-star mergers. These are predicted to eject material rich ...in heavy radioactive isotopes that can power an electromagnetic signal. This signal is luminous at optical and infrared wavelengths and is called a kilonova. The gravitational-wave source GW170817 arose from a binary neutron-star merger in the nearby Universe with a relatively well confined sky position and distance estimate. Here we report observations and physical modelling of a rapidly fading electromagnetic transient in the galaxy NGC 4993, which is spatially coincident with GW170817 and with a weak, short γ-ray burst. The transient has physical parameters that broadly match the theoretical predictions of blue kilonovae from neutron-star mergers. The emitted electromagnetic radiation can be explained with an ejected mass of 0.04 ± 0.01 solar masses, with an opacity of less than 0.5 square centimetres per gram, at a velocity of 0.2 ± 0.1 times light speed. The power source is constrained to have a power-law slope of -1.2 ± 0.3, consistent with radioactive powering from r-process nuclides. (The r-process is a series of neutron capture reactions that synthesise many of the elements heavier than iron.) We identify line features in the spectra that are consistent with light r-process elements (atomic masses of 90-140). As it fades, the transient rapidly becomes red, and a higher-opacity, lanthanide-rich ejecta component may contribute to the emission. This indicates that neutron-star mergers produce gravitational waves and radioactively powered kilonovae, and are a nucleosynthetic source of the r-process elements.
Electron microscopy, X-ray energy dispersive spectroscopy, and tomographic reconstructions were used to characterize a high entropy alloy predominantly composed of refractory elements. The ...intragranular microstructure was found to consist of a periodic two phase mixture, where a disordered bcc phase is aligned orthogonally in an ordered B2 phase. The phases were found to exhibit continuous lattice registry and an orientation relationship given by bcc// B2, {001}bcc//{001}B2. X-ray energy dispersive spectroscopy was used to determine the compositions of the phases, and spectral images were used in the tomographic reconstruction of the alloy to reveal the morphology and the elemental partitioning between phases.
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We present the one-year long observing campaign of SN 2012A which exploded in the nearby (9.8 Mpc) irregular galaxy NGC 3239. The photometric evolution is that of a normal Type IIP supernova, but the ...plateau is shorter and the luminosity not as constant as in other supernovae of this type. The absolute maximum magnitude, with M
B
= −16.23 ± 0.16 mag, is close to the average for SN IIP. Thanks also to the strong UV flux in the early phase, SN 2012A reached a peak luminosity of about 2 × 1042 erg s−1, which is brighter than those of other SNe with a similar 56Ni mass. The latter was estimated from the luminosity in the exponential tail of the light curve and found to be M(56Ni) = 0.011 ± 0.004 M, which is intermediate between standard and faint SN IIP. The spectral evolution of SN 2012A is also typical of SN IIP, from the early spectra dominated by a blue continuum and very broad (∼104 km s−1) Balmer lines, to the late-photospheric spectra characterized by prominent P-Cygni features of metal lines (Fe ii, Sc ii, Ba ii, Ti ii, Ca ii, Na i D). The photospheric velocity is moderately low, ∼3 × 103 km s−1 at 50 d, for the low optical depth metal lines. The nebular spectrum obtained 394 d after the shock breakout shows the typical features of SNe IIP and the strength of the O i doublet suggests a progenitor of intermediate mass, similar to SN 2004et (∼15 M). A candidate progenitor for SN 2012A has been identified in deep, pre-explosion K
′-band Gemini North Near-InfraRed Imager and Spectrometer images, and found to be consistent with a star with a bolometric magnitude −7.08 ± 0.36 (log L/L = 4.73 ± 0.14 dex). The magnitude of the recovered progenitor in archival images points towards a moderate-mass
star as the precursor of SN 2012A. The explosion parameters and progenitor mass were also estimated by means of a hydrodynamical model, fitting the bolometric light curve, the velocity and the temperature evolution. We found a best fit for a kinetic energy of 0.48 foe, an initial radius of 1.8 × 1013 cm and ejecta mass of 12.5 M. Even including the mass for the compact remnant, this appears fully consistent with the direct measurements given above.
We present an analysis of optical spectroscopically identified active galactic nuclei (AGN) down to a cluster magnitude of M
+ 1 in a sample of six self-similar Sloan Digital Sky Survey galaxy ...clusters at z ∼ 0.07. These clusters are specifically selected to lack significant substructure at bright limits in their central regions so that we are largely able to eliminate the local action of merging clusters on the frequency of AGN. We demonstrate that the AGN fraction increases significantly from the cluster centre to 1.5R
virial, but tails off at larger radii. If only comparing the cluster core region to regions at ∼ 2R
virial, no significant variation would be found. We compute the AGN fraction by mass and show that massive galaxies (log (stellarmass) > 10.7) are host to a systematically higher fraction of AGN than lower mass galaxies at all radii from the cluster centre. We attribute this deficit of AGN in the cluster centre to the changing mix of galaxy types with radius. We use the WHAN diagnostic to separate weak AGN from 'retired' galaxies in which the main ionization mechanism comes from old stellar populations. These retired AGN are found at all radii, while the mass effect is much more pronounced: we find that massive galaxies are more likely to be in the retired class. Further, we show that our AGN have no special position inside galaxy clusters - they are neither preferentially located in the infall regions nor situated at local maxima of galaxy density as measured with Σ5. However, we find that the most powerful AGN (with O iii equivalent widths <−10 Å) reside at significant velocity offsets in the cluster, and this brings our analysis into agreement with previous work on X-ray-selected AGN. Our results suggest that if interactions with other galaxies are responsible for triggering AGN activity, the time lag between trigger and AGN enhancement must be sufficiently long to obfuscate the encounter site and wipe out the local galaxy density signal.
We searched for an optical counterpart to the first gravitational-wave source discovered by LIGO (GW150914), using a combination of the Pan-STARRS1 wide-field telescope and the Public ESO ...Spectroscopic Survey of Transient Objects (PESSTO) spectroscopic follow-up programme. As the final LIGO sky maps changed during analysis, the total probability of the source being spatially coincident with our fields was finally only 4.2 per cent. Therefore, we discuss our results primarily as a demonstration of the survey capability of Pan-STARRS and spectroscopic capability of PESSTO. We mapped out 442 deg2 of the northern sky region of the initial map. We discovered 56 astrophysical transients over a period of 41 d from the discovery of the source. Of these, 19 were spectroscopically classified and a further 13 have host galaxy redshifts. All transients appear to be fairly normal supernovae (SNe) and AGN variability and none is obviously linked with GW150914. We illustrate the sensitivity of our survey by defining parametrized light curves with time-scales of 4, 20 and 40 d and use the sensitivity of the Pan-STARRS1 images to set limits on the luminosities of possible sources. The Pan-STARRS1 images reach limiting magnitudes of i
P1 = 19.2, 20.0 and 20.8, respectively, for the three time-scales. For long time-scale parametrized light curves (with full width half-maximum ≃40 d), we set upper limits of
$M_i \le -17.2^{-0.9}_{+1.4}$
if the distance to GW150914 is D
L = 400 ± 200 Mpc. The number of Type Ia SN we find in the survey is similar to that expected from the cosmic SN rate, indicating a reasonably complete efficiency in recovering SN like transients out to D
L = 400 ± 200 Mpc.
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