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The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
The Hubble Source Catalog (HSC) combines lists of sources detected on images obtained with the WFPC2, ACS and WFC3 instruments aboard the Hubble Space Telescope (HST) and now available in the Hubble Legacy Archive. The catalogue contains time-domain information for about two million of its sources detected using the same instrument and filter on at least five HST visits. The Hubble Catalog of Variables (HCV) aims to identify HSC sources showing significant brightness variations. A magnitude-dependent threshold in the median absolute deviation of photometric measurements (an outlier-resistant measure of light-curve scatter) is adopted as the variability detection statistic. It is supplemented with a cut in χred2 that removes sources with large photometric errors. A pre-processing procedure involving bad image identification, outlier rejection and computation of local magnitude zero-point corrections is applied to the HSC light-curves before computing the variability detection statistics. About 52 000 HSC sources have been identified as candidate variables, among which 7,800 show variability in more than one filter. Visual inspection suggests that ∼70% of the candidates detected in multiple filters are true variables, while the remaining ∼30% are sources with aperture photometry corrupted by blending, imaging artefacts or image processing anomalies. The candidate variables have AB magnitudes in the range 15–27m, with a median of 22m. Among them are the stars in our own and nearby galaxies, and active galactic nuclei.
Introduction: Hospital shootings are rare events that pose extreme and immediate risk to staff, patients and visitors. In 2015, the Ontario Hospital Association mandated all hospitals devise an armed assailant Code Silver protocol, an alert issued to mitigate risk and manage casualties. We describe the design and implementation of ASSIST (Active Shooter Simulation In-Situ Training), an institutional, full-scale hybrid simulation exercise to test hospital-wide response and readiness for an active shooter event, and identify latent safety threats (LSTs) related to the high-stakes alert and transport of internal trauma patients. Methods: A hospital-wide in-situ simulation was conducted at a Level 1 trauma centre in downtown Toronto. The two-hour exercise tested a draft Code Silver policy created by the hospital’s disaster planning committee, to identify missing elements and challenges with protocol implementation. The scenario consisted of a shooting during a hospital meeting with three casualties: a manikin with life-threatening head and abdomen gunshot wounds (GSWs), a standardized patient (SP) with hypotension from an abdominal GSW, and a second SP with minor injuries and significant psychological distress. The exercise piloted the use of a novel emergency department (ED)-based medical exfiltration team to transport internal victims to the trauma bay. The on-call trauma team provided medical care. Ethnographic observation of response by municipal police, hospital security, logistics and medical personnel was completed. LSTs were evaluated and categorized using video framework analysis. Feasibility was measured through debriefings and impact on ED workflow. Results: Seventy-six multidisciplinary medical and logistical staff and learners participated in this exercise. Using a framework analysis, the following LSTs were identified: 1) Significant communication difficulties within the shooting area, 2) Safe access and transport for internal casualties, 3) Difficulty accessing hospital resources (blood bank) 4) Challenges coordinating response with external agencies (police, EMS) and 5) Delay in setting up an off-site command centre. Conclusion: In situ simulation represents a novel approach to the development of Code Silver alert processes. Findings from ethnographic observations and a video-based analysis form a framework to address safety, logistical and medical response considerations.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
Public Health England conducts enhanced national surveillance of tetanus, a potentially life-threatening vaccine-preventable disease. A standardized questionnaire was used to ascertain clinical and demographic details of individuals reported with clinically suspected tetanus. The 96 cases identified between 2001 and 2014 were analysed. The average annual incidence was 0·13/million (95% confidence interval 0·10–0·16) of which 50·0% were male. Where reported, 70·3% of injuries occurred in the home/garden (45/64). Overall, 40·3% (31/77) cases were in people who inject drugs (PWID), including a cluster of 22 cases during 2003–2004. Where known (n = 68), only 8·8% were age-appropriately immunized. The overall case-fatality rate was 11·0% (9/82). All tetanus-associated deaths occurred in adults aged >45 years, none of whom were fully immunized. Due to the success of the childhood immunization programme, tetanus remains a rare disease in England with the majority of cases occurring in older unimmunized or partially immunized adults. Minor injuries in the home/garden were the most commonly reported likely sources of infection, although cases in PWID increased during this period. It is essential that high routine vaccine coverage is maintained and that susceptible individuals, particularly older adults, are protected through vaccination and are offered timely post-exposure management following a tetanus-prone wound.
We present a list of bright (< 17 mag) southern QSOs and bright (< 11 mag) stars that may be suitable for the Hubble Space Telescope link between the Hipparcos astrometric reference frame and the VLBI extragalactic frame. The QSOs have been selected from various lists of radio objects and identifications. The stars have been selected from the Strasbourg (CDS) data base and from the Preliminary Second Cape Photographic Catalogue, and supplemented with stars measured from the SERC IIIa-J Schmidt survey. The list of QSOs and stars have been included in the Hipparcos and HST schedule of observations.
The Evolutionary Map of the Universe (EMU) is a proposed radio continuum survey
of the Southern Hemisphere up to declination + 30°, with the Australian
Square Kilometre Array Pathfinder (ASKAP). EMU will use an automated source
identification and measurement approach that is demonstrably optimal, to
maximise the reliability and robustness of the resulting radio source
catalogues. As a step toward this goal we conducted a “Data
Challenge” to test a variety of source finders on simulated images. The
aim is to quantify the accuracy and limitations of existing automated source
finding and measurement approaches. The Challenge initiators also tested the
current ASKAPsoft source-finding tool to establish how it could benefit from
incorporating successful features of the other tools. As expected, most finders
show completeness around 100% at ≈ 10σ dropping to about 10% by
≈ 5σ. Reliability is typically close to 100% at ≈
10σ, with performance to lower sensitivities varying between finders. All
finders show the expected trade-off, where a high completeness at low
signal-to-noise gives a corresponding reduction in reliability, and vice versa.
We conclude with a series of recommendations for improving the performance of
the ASKAPsoft source-finding tool.
This paper, a report by the Clinical Governance and Audit Committee of the Scottish Otolaryngological Society, presents a consensus view of the minimal requirements for ENT clinics in National Health Service hospitals.
Results and conclusion:
The provision of adequate equipment and staff has gained increasing importance as the vast majority of ENT procedures can be safely performed in the out-patient or office setting.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Departing from accounts of minority group politics that focus on the role of group identity in advancing group members’ common interests, we investigate political decisions involving tradeoffs between group interests and simple self-interest. Using the case of black Americans, we investigate crystallized group norms about politics, internalized beliefs about group solidarity, and mechanisms for enforcing both through social pressure. Through a series of novel behavioral experiments that offer black subjects individual incentives to defect from the position most favored by black Americans as a group, we test the effects of social pressure to conform. We find that racialized social pressure and internalized beliefs in group solidarity are constraining and depress self-interested behavior. Our results speak to a common conflict—choosing between maximizing group interests and self-interest—and yet also offer specific insight into how blacks remain so homogeneous in partisan politics despite their growing ideological and economic variation.
Meta-analyses suggest that reboxetine may be less effective than other antidepressants. Such comparisons may be biased by lower adherence to reboxetine and subsequent handling of missing outcome data. This study illustrates how to adjust for differential non-adherence and hence derive an unbiased estimate of the efficacy of reboxetine compared with citalopram in primary care patients with depression.
A structural mean modelling (SMM) approach was used to generate adherence-adjusted estimates of the efficacy of reboxetine compared with citalopram using GENetic and clinical Predictors Of treatment response in Depression (GENPOD) trial data. Intention-to-treat (ITT) analyses were performed to compare estimates of effectiveness with results from previous meta-analyses.
At 6 weeks, 92% of those randomized to citalopram were still taking their medication, compared with 72% of those randomized to reboxetine. In ITT analysis, there was only weak evidence that those on reboxetine had a slightly worse outcome than those on citalopram [adjusted difference in mean Beck Depression Inventory (BDI) scores: 1.19, 95% confidence interval (CI) –0.52 to 2.90, p = 0.17]. There was no evidence of a difference in efficacy when differential non-adherence was accounted for using the SMM approach for mean BDI (–0.29, 95% CI –3.04 to 2.46, p = 0.84) or the other mental health outcomes.
There was no evidence of a difference in the efficacy of reboxetine and citalopram when these drugs are taken and tolerated by depressed patients. The SMM approach can be implemented in standard statistical software to adjust for differential non-adherence and generate unbiased estimates of treatment efficacy for comparisons of two (or more) active interventions.
In a cross-sectional study, data from records of cattle slaughtered over a 1-year period at a large abattoir in South West England were analysed using an ordered category response model to investigate the inter-relationships between age, sex and breed on development of the permanent anterior (PA) teeth. Using the model, transition points at which there was a 50% probability of membership of each category of paired PA teeth were identified. Data from ∼60 000 animals were initially analysed for age and sex effect. The age transition was found to be ∼23 months moving from zero to two teeth; 30 months for two to four teeth; 37 months for four to six teeth and 42 months for six to eight teeth. Males were found to develop, on average, ∼22 days earlier than females across all stages. A reduced data set of ∼23 000 animals registered as pure-bred only was used to compare breed and type interactions and to investigate sex effects within the sub-categories. Breeds were grouped into dairy and beef-type and beef breeds split into native and continental. It was found that dairy-types moved through the transition points earlier than beef-types across all stages (interval varying between ∼8 and 12 weeks) and that collectively, native beef breeds moved through the transition points by up to 3 weeks earlier than the continental beef breeds. Interestingly, in contrast to beef animals, dairy females matured before dairy males. However, the magnitude of the difference between dairy females and males diminished at the later stages of development. Differences were found between breeds. Across the first three stages, Ayrshires and Guernseys developed between 3 and 6 weeks later than Friesian/Holsteins and Simmental, Limousin and Blonde Aquitaine 6 and 8 weeks later than Aberdeen Angus. Herefords, Charolais and South Devon developed later but by a smaller interval and Red Devon and Galloway showed the largest individual effect with transition delayed by 8 to 12 weeks.
The cold, dry, and stable air above the summits of the Antarctic plateau provides the best ground-based observing conditions from optical to sub-millimetre wavelengths to be found on the Earth. Pathfinder for an International Large Optical Telescope (PILOT) is a proposed 2 m telescope, to be built at Dome C in Antarctica, able to exploit these conditions for conducting astronomy at optical and infrared wavelengths. While PILOT is intended as a pathfinder towards the construction of future grand-design facilities, it will also be able to undertake a range of fundamental science investigations in its own right. This paper provides the performance specifications for PILOT, including its instrumentation. It then describes the kinds of projects that it could best conduct. These range from planetary science to the search for other solar systems, from star formation within the Galaxy to the star formation history of the Universe, and from gravitational lensing caused by exo-planets to that produced by the cosmic web of dark matter. PILOT would be particularly powerful for wide-field imaging at infrared wavelengths, achieving near diffraction-limited performance with simple tip–tilt wavefront correction. PILOT would also be capable of near diffraction-limited performance in the optical wavebands, as well be able to open new wavebands for regular ground-based observation, in the mid-IR from 17 to 40 μm and in the sub-millimetre at 200 μm.
Deficits in executive function (EF) are reported to occur in individuals with Klinefelter syndrome (XXY). The degree of impairment, if any, is variable and the nature of these deficits has not been clearly elucidated in young males. In this report, we (a) examine EF skills using multiple tasks in a non-clinic referred group of youth with XXY, (b) describe the extent of EF weaknesses in XXY when this group is compared with typical males of a similar SES or typical males with similar verbal abilities, and (c) evaluate the contribution of comorbid attention-deficit/hyperactivity disorder (ADHD) to EF skills. The sample included 27 males with XXY (ages 9–25), 27 typically developing age- and vocabulary-matched males, and 22 age- and socioeconomic status-matched males. EF tasks included Verbal Fluency, the Trail Making Test, and the CANTAB Spatial Working Memory and Stockings of Cambridge tasks. Mixed model analysis of variance was used to compare the groups on EF tasks and revealed a main effect of group but no group by task interaction. Overall, the XXY group performed less well than both control groups, but performance did not differ significantly as a function of task. ADHD comorbidity in males with XXY was related to poorer EF skills. (JINS, 2011, 17, 522–530)
The science of extra-solar planets is one of the most rapidly changing areas of astrophysics and since 1995 the number of planets known has increased by almost two orders of magnitude. A combination of ground-based surveys and dedicated space missions has resulted in 560-plus planets being detected, and over 1200 that await confirmation. NASA's Kepler mission has opened up the possibility of discovering Earth-like planets in the habitable zone around some of the 100,000 stars it is surveying during its 3 to 4-year lifetime. The new ESA's Gaia mission is expected to discover thousands of new planets around stars within 200 parsecs of the Sun. The key challenge now is moving on from discovery, important though that remains, to characterisation: what are these planets actually like, and why are they as they are?
In the past ten years, we have learned how to obtain the first spectra of exoplanets using transit transmission and emission spectroscopy. With the high stability of Spitzer, Hubble, and large ground-based telescopes the spectra of bright close-in massive planets can be obtained and species like water vapour, methane, carbon monoxide and dioxide have been detected. With transit science came the first tangible remote sensing of these planetary bodies and so one can start to extrapolate from what has been learnt from Solar System probes to what one might plan to learn about their faraway siblings. As we learn more about the atmospheres, surfaces and near-surfaces of these remote bodies, we will begin to build up a clearer picture of their construction, history and suitability for life.
The Exoplanet Characterisation Observatory, EChO, will be the first dedicated mission to investigate the physics and chemistry of Exoplanetary Atmospheres. By characterising spectroscopically more bodies in different environments we will take detailed planetology out of the Solar System and into the Galaxy as a whole.
EChO has now been selected by the European Space Agency to be assessed as one of four M3 mission candidates.