296 research outputs found

    From Prevent to Protect and Prepare: The Manchester Arena Attack and Shifting Priorities in the United Kingdom’s Counter-Terrorism Strategy (CONTEST)

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    This article analyses the UK’s counter-terrorism strategy CONTEST from a Disaster Management perspective. The article argues that since the Manchester Arena attack in May 2017, there has been a reorientation in CONTEST away from a primary focus on Prevent towards a greater concern with Protect and Prepare. We argue this move should be welcome, given it provides the wider benefit of embedding emergency preparedness and improving multi-agency response to all types of major incident in the UK. The article analyses the inquiry into the Manchester Arena attack to identify three important lessons for the development of CONTEST

    Trade-offs between the natural environment and recreational infrastructure:A case study about peatlands under different management scenarios

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    The importance of peatlands for conservation and provision of public services has been well evidenced in the last years, especially in relation to their contribution to the net zero carbon emission agenda. However, little is known about the importance of recreation relative to conservation and their trade-offs. In this paper we address this knowledge gap by exploring the trade-offs between natural properties of peatlands and recreational infrastructures for different categories of recreationists (walkers, cyclists, anglers, and birdwatchers) of an open heather moors and peatlands landscape. We do so building on a series of management scenarios formulated through participatory methods and applying choice experiment related to an Area of Outstanding Natural Beauty and UNESCO Global Geopark in the UK. Results show a high degree of heterogeneity in landscape preferences across different user groups. Recreationists had a higher appreciation for semi-natural habitats compared to pristine or restored peatland (e.g., land rewetting). Walkers and cyclists were more sensitive to changes in the availability of recreational facilities than to environmental quality, while anglers’ and birdwatchers’ preferences were more aligned with values promoted by restoration policies. Overall, our results point to a potential value conflict between benefits generated by conservation and the benefits valued most by some groups of recreationists. To maximise success conflicts like the one revealed here need to be considered in strategies that provide a central role for peatlands in net zero climate mitigation strategies

    The Early Ultraviolet Light-Curves of Type II Supernovae and the Radii of Their Progenitor Stars

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    We present a sample of 34 normal SNe II detected with the Zwicky Transient Facility, with multi-band UV light-curves starting at t≀4t \leq 4 days after explosion, as well as X-ray detections and upper limits. We characterize the early UV-optical colors and provide prescriptions for empirical host-extinction corrections. We show that the t>2 t > 2\,days UV-optical colors and the blackbody evolution of the sample are consistent with the predictions of spherical phase shock-cooling (SC), independently of the presence of `flash ionization" features. We present a framework for fitting SC models which can reproduce the parameters of a set of multi-group simulations without a significant bias up to 20% in radius and velocity. Observations of about half of the SNe II in the sample are well-fit by models with breakout radii <1014 <10^{14}\,cm. The other half are typically more luminous, with observations from day 1 onward that are better fit by a model with a large >1014 >10^{14}\,cm breakout radius. However, these fits predict an early rise during the first day that is too slow. We suggest these large-breakout events are explosions of stars with an inflated envelope or a confined CSM with a steep density profile, at which breakout occurs. Using the X-ray data, we derive constraints on the extended (∌1015\sim10^{15} cm) CSM density independent of spectral modeling, and find most SNe II progenitors lose <10−4M⊙ yr−1<10^{-4} M_{\odot}\, \rm yr^{-1} a few years before explosion. This provides independent evidence the CSM around many SNe II progenitors is confined. We show that the overall observed breakout radius distribution is skewed to higher radii due to a luminosity bias. We argue that the 66−22+11%66^{+11}_{-22}\% of red supergiants (RSG) explode as SNe II with breakout radii consistent with the observed distribution of field RSG, with a tail extending to large radii, likely due to the presence of CSM.Comment: Submitted to ApJ. Comments are welcome at [email protected] or [email protected]

    GA-NIFS: Black hole and host galaxy properties of two z≃\simeq6.8 quasars from the NIRSpec IFU

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    Integral Field Spectroscopy (IFS) with JWST NIRSpec will significantly improve our understanding of the first quasars, by providing spatially resolved, infrared spectroscopic capabilities which cover key rest-frame optical emission lines that have been previously unobservable. Here we present our results from the first two z>6 quasars observed as a part of the Galaxy Assembly with NIRSpec IFS (GA-NIFS) GTO program, DELS J0411-0907 at z=6.82 and VDES J0020-3653 at z=6.86. By observing the HÎČ\beta, [OIII], and Hα\alpha emission lines in these high-z quasars for the first time, we measure accurate black hole masses, MBH=1.85e9M_{\rm{BH}}=1.85e9 and 2.9e92.9e9M⊙_\odot, corresponding to Eddington ratios of λEdd=0.8\lambda_{\rm{Edd}}=0.8 and 0.4 for DELS J0411-0907 and VDES J0020-3653 respectively. These provide a key comparison for existing estimates from the more uncertain MgII line. We perform quasar-host decomposition using models of the quasars' broad lines to measure the underlying host galaxies. We also discover multiple emission line regions surrounding each of the host galaxies, which are likely companion galaxies undergoing mergers with these hosts. We measure the star formation rates, excitation mechanisms, and dynamical masses of the hosts and companions, measuring the MBH/MdynM_{\rm{BH}}/M_{\rm{dyn}} ratios at high-z using these estimators for the first time. DELS J0411-0907 and VDES J0020-3653 both lie above the local black hole--host mass relation, and are consistent with the existing observations of z≳6z\gtrsim6 quasar host galaxies with ALMA. We detect ionized outflows in [OIII] and HÎČ\beta from both quasars, with mass outflow rates of 58 and 525 M⊙_{\odot}/yr for DELS J0411-0907 and VDES J0020-3653, much larger than their host star formation rates of <33 and <54 M⊙_\odot/yr. This work highlights the exceptional capabilities of the JWST NIRSpec IFU for observing quasars in the early Universe.Comment: 27 pages, 10 figures. Resubmitted to A&A after significant revisions. If you have cited values from our first version, please check this version and update accordingly, as many values have changed slightly thanks to improvements in our analysi

    Combination lithium and Divalproex sodium in pediatric bipolarity

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    ABSTRACT Objective: It has been reported that bipolar disorder may become less responsive to previously effective treatment with each symptomatic relapse. The primary goal of this study was to assess the rate of restabilization after the resumption of lithium (L

    The prevalence and influence of circumstellar material around hydrogen-rich supernova progenitors

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    Narrow transient emission lines (flash-ionization features) in early supernova (SN) spectra trace the presence of circumstellar material (CSM) around the massive progenitor stars of core-collapse SNe. The lines disappear within days after the SN explosion, suggesting that this material is spatially confined, and originates from enhanced mass loss shortly (months to a few years) prior to explosion. We performed a systematic survey of H-rich (Type II) SNe discovered within less than two days from explosion during the first phase of the Zwicky Transient Facility (ZTF) survey (2018-2020), finding thirty events for which a first spectrum was obtained within <2< 2 days from explosion. The measured fraction of events showing flash ionisation features (>36%>36\% at 95%95\% confidence level) confirms that elevated mass loss in massive stars prior to SN explosion is common. We find that SNe II showing flash ionisation features are not significantly brighter, nor bluer, nor more slowly rising than those without. This implies that CSM interaction does not contribute significantly to their early continuum emission, and that the CSM is likely optically thin. We measured the persistence duration of flash ionisation emission and find that most SNe show flash features for ≈5\approx 5 days. Rarer events, with persistence timescales >10>10 days, are brighter and rise longer, suggesting these may be intermediate between regular SNe II and strongly-interacting SNe IIn

    A Large Fraction of Hydrogen-rich Supernova Progenitors Experience Elevated Mass Loss Shortly Prior to Explosion

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    Spectroscopic detection of narrow emission lines traces the presence of circumstellar mass distributions around massive stars exploding as core-collapse supernovae. Transient emission lines disappearing shortly after the supernova explosion suggest that the material spatial extent is compact and implies an increased mass loss shortly prior to explosion. Here, we present a systematic survey for such transient emission lines (Flash Spectroscopy) among Type II supernovae detected in the first year of the Zwicky Transient Facility survey. We find that at least six out of ten events for which a spectrum was obtained within two days of the estimated explosion time show evidence for such transient flash lines. Our measured flash event fraction (&gt;30% at 95% confidence level) indicates that elevated mass loss is a common process occurring in massive stars that are about to explode as supernovae
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