296 research outputs found
From Prevent to Protect and Prepare: The Manchester Arena Attack and Shifting Priorities in the United Kingdomâs Counter-Terrorism Strategy (CONTEST)
This article analyses the UKâs 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
Trade-offs between the natural environment and recreational infrastructure:A case study about peatlands under different management scenarios
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 anglersâ and birdwatchersâ 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
Trade-offs between the natural environment and recreational infrastructure:A case study about peatlands under different management scenarios
The Early Ultraviolet Light-Curves of Type II Supernovae and the Radii of Their Progenitor Stars
We present a sample of 34 normal SNe II detected with the Zwicky Transient
Facility, with multi-band UV light-curves starting at 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 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 cm. The other
half are typically more luminous, with observations from day 1 onward that are
better fit by a model with a large 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
( cm) CSM density independent of spectral modeling, and find most
SNe II progenitors lose 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 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 z6.8 quasars from the NIRSpec IFU
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 H, [OIII], and H
emission lines in these high-z quasars for the first time, we measure accurate
black hole masses, and M, corresponding to
Eddington ratios of 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 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 quasar host galaxies with ALMA. We detect
ionized outflows in [OIII] and H from both quasars, with mass outflow
rates of 58 and 525 M/yr for DELS J0411-0907 and VDES J0020-3653,
much larger than their host star formation rates of <33 and <54 M/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
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
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 days from
explosion. The measured fraction of events showing flash ionisation features
( at 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 days.
Rarer events, with persistence timescales 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
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 (>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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