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We present the first Faraday rotation measure (RM) grid study of an individual low-mass cluster -- the Fornax cluster -- which is presently undergoing a series of mergers. Exploiting commissioning data for the POlarisation Sky Survey of the Universe's Magnetism (POSSUM) covering a $\sim34$ square degree sky area using the Australian Square Kilometre Array Pathfinder (ASKAP), we achieve an RM grid density of $\sim25$ RMs per square degree from a 280 MHz band centred at 887 MHz, which is similar to expectations for forthcoming GHz-frequency all-sky surveys. We thereby probe the extended magnetoionic structure of the cluster in unprecedented detail. We find that the scatter in the Faraday RM of confirmed background sources is increased by $16.8\pm2.4$ rad m$^{-2}$ within 1 degree (360 kpc) projected distance to the cluster centre, which is 2--4 times more extended than the presently-detectable X-ray-emitting intracluster medium (ICM). The Faraday-active plasma is more massive than the X-ray-emitting ICM, with an average density that broadly matches expectations for the Warm-Hot Intergalactic Medium. The morphology of the Faraday depth enhancement exhibits the classic morphology of an astrophysical bow shock on the southwest side of the main Fornax cluster, and an extended, swept-back wake on the northeastern side. Our favoured explanation is an ongoing merger between the main cluster and a sub-cluster to the southwest. The shock's Mach angle and stand-off distance lead to a self-consistent transonic merger speed with Mach 1.06. The region hosting the Faraday depth enhancement shows a decrement in both total and polarised intensity. We fail to identify a satisfactory explanation for this; further observations are warranted. Generally, our study illustrates the scientific returns that can be expected from all-sky grids of discrete sources generated by forthcoming all-sky radio surveys., Comment: Accepted for publication in PASA. 27 pages, 14 figures, 1 table

We describe the performance of the Boolardy Engineering Test Array (BETA), the prototype for the Australian Square Kilometre Array Pathfinder telescope ASKAP. BETA is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarization 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 BETA's performance: sensitivity, beam characteristics, polarimetric properties and image quality. We summarise the astronomical science that it has produced and draw lessons from operating BETA that will be relevant to the commissioning and operation of the final ASKAP telescope., Accepted for publication in PASA

The Variables and Slow Transients Survey (VAST) on the Australian Square Kilometre Array Pathfinder (ASKAP) is designed to detect highly variable and transient radio sources on timescales from 5 s to$\sim\!5$yr. In this paper, we present the survey description, observation strategy and initial results from the VAST Phase I Pilot Survey. This pilot survey consists of$\sim\!162$h of observations conducted at a central frequency of 888 MHz between 2019 August and 2020 August, with a typical rms sensitivity of$0.24\ \mathrm{mJy\ beam}^{-1}$and angular resolution of$12-20$arcseconds. There are 113 fields, each of which was observed for 12 min integration time, with between 5 and 13 repeats, with cadences between 1 day and 8 months. The total area of the pilot survey footprint is 5 131 square degrees, covering six distinct regions of the sky. An initial search of two of these regions, totalling 1 646 square degrees, revealed 28 highly variable and/or transient sources. Seven of these are known pulsars, including the millisecond pulsar J2039–5617. Another seven are stars, four of which have no previously reported radio detection (SCR J0533–4257, LEHPM 2-783, UCAC3 89–412162 and 2MASS J22414436–6119311). Of the remaining 14 sources, two are active galactic nuclei, six are associated with galaxies and the other six have no multi-wavelength counterparts and are yet to be identified.

Informed by the Ecological and Health Belief models, the manualized Stroll Safe program addresses the unmet need of a targeted outdoors falls prevention program. We examined the efficacy of the program in partnership with eight Naturally Occurring Retirement Community program sites in one U.S city (N=86). Participants age 60 and older with a history of falls or a fear of falling were recruited. Community sites were randomly assigned to the treatment or wait list control group. Results of independent samples t-tests reveal a statistically significant improvement in knowledge of outdoor fall risks and safe community mobility strategy use for the treatment group as compared to the wait list control group on the Outdoor Falls Questionnaire (OFQ) and Falls Behavioral Scale for the Older Person (FaB) (ps

Active M-dwarfs are known to produce bursty radio emission, and multi-wavelength studies have shown that Solar-like magnetic activity occurs in these stars. However, coherent bursts from active M-dwarfs have often been difficult to interpret in the Solar activity paradigm. We present Australian Square Array Pathfinder (ASKAP) observations of UV Ceti at a central frequency of 888 MHz. We detect several periodic, coherent pulses occurring over a timescale consistent with the rotational period of UV Ceti. The properties of the pulsed emission show that they originate from the electron cyclotron maser instability, in a cavity $\sim7$ orders of magnitude less dense than the mean coronal density at the estimated source altitude. These results confirm that auroral activity can occur in active M-dwarfs, suggesting that these stars mark the beginning of the transition from Solar-like to auroral magnetospheric behaviour. These results demonstrate the capabilities of ASKAP for detecting polarized, coherent bursts from active stars and other systems., Comment: 15 pages, 8 figures, 1 table. Accepted for publication in Monthly Notices of the Royal Astronomical Society

The AC and DC dielectric properties of hydrofluoroethers (HFE) [C3F7 OCH3 ] and fluorinated ketone (FK) [C2F5 C(O)CF(CF3)2] have been characterised by dielectric spectroscopy and DC conductivity at different temperatures. Results show that DC conductivity and imaginary permittivity of both fluids are positively correlated with increasing temperature. However, the real permittivity decreases with increasing temperature. The breakdown voltages of HFE and FK at 295 K are∼10 kV mm−1 . Reducing temperature is an effective method to increase the breakdown voltage of the FK coolant, but the breakdown voltage of HFE is less temperature dependent. Finally, as expected repeated breakdown had no significant effect on the AC dielectric strength of both liquids.

Aims There are many challenges in delivering an orthopaedic training programme in Sierra Leone, West Africa, including human resource and equipment constraints. We provide a reflective analysis of adaptive strategies to overcome these. Methods An orthopaedic surgical training course was delivered in preparation for a clinical trial in Connaught Hospital, Freetown, Sierra Leone. The trial examines the implementation of Ilizarov frame fixation for tibia fractures in adults. Results Whilst it is possible to deliver a high-quality course in Sierra Leone, a significant amount of prior planning and preparation, including adaptive and contingency strategies, is required to achieve the desired outcome. Conclusions With the Royal Navy increasing its global reach, including deployment of new aircraft carriers, there are increasing opportunities to deliver medical training in low and middle-income countries in both the military and civilian sector. We believe this article may be useful for service and civilian practitioners intending to deliver education and training around the world.

In this paper we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers 31 square degrees at 800 MHz. As a two-dimensional array of 36x12m antennas, with baselines ranging from 22m to 6km, ASKAP also has excellent snapshot imaging capability and 10 arcsecond resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 MHz and 1800 MHz and is expected to facilitate great advances in our understanding of galaxy formation, cosmology and radio transients while opening new parameter space for discovery of the unknown., 38 pages, 24 figures, accepted for publication in PASA

Supplemental material, sj-docx-3-otj-10.1177_15394492211023192 for Out-of-Home Activities and Health in Older Adults: A Scoping Review by Shlomit Rotenberg, Heather Fritz, Tracy Chippendale, Catherine Lysack and Malcolm Cutchin in OTJR: Occupation, Participation and Health

Supplemental material, sj-docx-2-otj-10.1177_15394492211023192 for Out-of-Home Activities and Health in Older Adults: A Scoping Review by Shlomit Rotenberg, Heather Fritz, Tracy Chippendale, Catherine Lysack and Malcolm Cutchin in OTJR: Occupation, Participation and Health

BACKGROUND: Sepsis is associated with a 36% mortality rate, rising to 50% for septic shock. Currently, when an East Midlands Ambulance Service clinician recognises ‘red flag’ sepsis, only the oxygen and fluid elements of the ‘Sepsis Six’ care bundle are delivered, omitting the antibiotic therapy. For a patient in septic shock, every hour’s delay in antibiotic therapy is associated with a 7.6% increase in mortality. Ambulance clinicians are therefore appropriately placed to assess and commence treatment at the earliest point of recognition. The aim of this evaluation was to assess the feasibility of training paramedics to recognise ‘red flag’ sepsis, obtain blood cultures and administer a broad spectrum antibiotic, meropenem, to patients in the pre-hospital environment. METHODS: A prospective six-month feasibility pilot evaluation was conducted in May 2016. Paramedics were trained and given access to a broad spectrum antibiotic, meropenem, along with a patient group direction to administer the antibiotic to ‘red flag’ sepsis patients. Training included sepsis recognition, taking of blood cultures and patient group direction compliance. RESULTS: Twenty paramedics volunteered and successfully completed the training. Of the 113 patients that were identified as ‘red flag’ sepsis, 107 (94.6%) were confirmed as infected by the receiving hospital. Ninety-eight blood samples were successfully drawn by study paramedics, with only seven (7.1%) reported as contaminated samples, compared with 8.5% of samples taken by staff in the receiving ED during the same time period. Ninety patients (80%) assessed by paramedics as meeting the criteria were treated with meropenem, and patient group direction compliance was 100%. CONCLUSION: Paramedics can safely deliver pre-hospital antibiotics to patients with ‘red flag’ sepsis and obtain blood cultures prior to administration, with a contamination rate comparable with local hospitals, following a short training course.

Effective physician-nurse communication is critical to patient safety, yet internal medicine trainees are rarely given feedback on this skill. In order to address this gap, we developed a 4-week simulated paging curriculum for senior medical students. Standardized Registered Nurses administered five acute inpatient paging cases to students via telephone and scored communication on a 10-point global scale (1 = highly ineffective to 10 = highly effective) and seven communication domains using a 5-point Likert-type scale. The domains included precision/clarity, instructive, directing, assertive, ability to solicit information, engaged, and structured communication. Students received verbal and written feedback from the nurses on communication skills and clinical decision-making. Our primary goal was to determine if student-nurse communication improved throughout the curriculum. Data were analyzed using multivariate ANOVAs with repeated measures. Twenty-seven students participated. Global communication scores increased significantly from case 1 to case 5 (7.1 to 8.7, p < .01). The following communication domains increased significantly: precision (3.8 to 4.4, p < .01), instructive (3.6 to 4.7, p < .01), directing (4.0 to 4.6, p = .02), assertiveness (4.0 to 4.7, p = .04), engaged (4.1 to 4.7, p < .01). In conclusion, this curriculum can be an innovative approach to improve physician-nurse communication using standardized registered nurses to deliver structured feedback to medical trainees.

Accurate instrumental bandpass corrections are essential for the reliable interpretation of spectral lines from targeted and survey-mode observations with radio interferometers. Bandpass correction is typically performed by comparing measurements of a strong calibrator source to an assumed model, typically an isolated point source. The wide field-of-view and high sensitivity of modern interferometers means that additional sources are often detected in observations of calibrators. This can introduce errors into bandpass corrections and subsequently the target data if not properly accounted for. Focusing on the standard calibrator PKS B1934-638, we perform simulations to asses this effect by constructing a wide-field sky model. The cases of ASKAP (0.7-1.9 GHz), MeerKAT (UHF: 0.58-1.05 GHz; L-band: 0.87-1.67 GHz) and Band 2 (0.95-1.76 GHz) of SKA-MID are examined. The use of a central point source model during bandpass calibration is found to impart amplitude errors into spectra measured by the precursor instruments at the ~0.2-0.5% level dropping to ~0.01% in the case of SKA-MID. This manifests itself as ripples in the source spectrum, the behaviour of which is coupled to the distribution of the array baselines, the solution interval, the primary beam size, the hour-angle of the calibration scan, as well as the weights used when imaging the target. Calibration pipelines should routinely employ complete field models for standard calibrators to remove this potentially destructive contaminant from the data, a recommendation we validate by comparing our simulation results to a MeerKAT scan of PKS B1934-638, calibrated with and without our expanded sky model., 11 pages, 10 figures, accepted for publication in MNRAS

Obscuration of quasars by accreted gas and dust, or dusty intervening galaxies, can cause active galactic nuclei (AGN) to be missed in optically-selected surveys. Radio observations can overcome this dust bias. In particular, radio surveys searching for HI absorption inform us on how the AGN can impact on the cold neutral gas medium within the host galaxy, or the population of intervening galaxies through the observed line of sight gas kinematics. We present the results of a HI absorption line survey at $0.4 < z < 1$ towards 34 obscured quasars with the Australian SKA Pathfinder (ASKAP) commissioning array. We detect three HI absorption lines, with one of these systems previously unknown. Through optical follow-up for two sources, we find that in all detections the HI gas is associated with the AGN, and hence that these AGN are obscured by material within their host galaxies. Most of our sample are compact, and in addition, are either gigahertz peaked spectrum (GPS), or steep spectrum (CSS) sources, both thought to represent young or recently re-triggered radio AGN. The radio spectral energy distribution classifications for our sample agree with galaxy evolution models in which the obscured AGN has only recently become active. Our associated HI detection rate for GPS and compact SS sources matches those of other surveys towards such sources. We also find shallow and asymmetric HI absorption features, which agrees with previous findings that the cold neutral medium in compact radio galaxies is typically kinematically disturbed by the AGN., Accepted for publication in MNRAS. 19 pages, 8 figures

Optics is an important subfield of physics required for instrument design and used in a variety of other disciplines, especially subjects that intersect the life sciences. Students from a variety of disciplines and backgrounds should be educated in the basics of optics to train the next generation of interdisciplinary researchers and instrumentalists who will push the boundaries of discovery or create inexpensive optical-based diagnostics. We present an experimental curriculum developed to teach students the basics of geometric optics, including ray and wave optics. The students learn these concepts in an active, hands-on manner through designing, building, and testing a homebuilt light microscope made from component parts. We describe the experimental equipment and basic measurements students can perform to learn these basic optical principles focusing on good optical design techniques, testing, troubleshooting, and iterative design. Students are also exposed to fundamental concepts of measurement uncertainty inherent in all experimental systems. The project students build is open and versatile to allow advanced projects, such as epifluorescence. We also describe how the equipment and curriculum can be flexibly used for an undergraduate level optics course, an advanced laboratory course, and graduate-level training modules or short courses.

Aims: Outdoor falls can result in significant challenges to the health and well-being of older adults. Therefore, factors associated with outdoor fall risk warrant attention in research and clinica...