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We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
Large area, parallel beams of x-rays are potentially useful in many diffraction, imaging and other x-ray analysis applications. Diffraction, in typical experiments, uses only a small portion of the incident beam that is within a limited “rocking curve” of the crystal capable of diffracting, although the whole crystal may be illuminated by the incident beam. Signal intensity can be increased if the ”whole” crystal can be made to diffract simultaneously. Similarly for imaging, improved results also are possible if divergent beams are replaced with nearly parallel ones. Production of parallel beams of large areal extent has not been simple. Often this meant that the source had to be placed at great distances from the sample, reducing the incident intensity. Sometimes, asymmetric cuts of crystals can be used to increase beam cross-sectional areas.
Production of parallel beams of large area! extent has not been simple. Often this meant that the source had to be placed at great distances from the sample, reducing the incident intensity. Sometimes, asymmetric cuts of crystals can be used to increase beam cross-sectional areas.
The extent to which exposure to childhood sexual and physical abuse increases the risk of psychotic experiences in adulthood is currently unclear.
To examine the relationship between childhood sexual and physical abuse and psychotic experiences in adulthood taking into account potential confounding and time-dynamic covariate factors.
Data were from a cohort of 1265 participants studied from birth to 35 years. At ages 18 and 21, cohort members were questioned about childhood sexual and physical abuse. At ages 30 and 35, they were questioned about psychotic experiences (symptoms of abnormal thought and perception). Generalised estimating equation models investigated covariation of the association between abuse exposure and psychotic experiences including potential confounding factors in childhood (socioeconomic disadvantage, adverse family functioning) and time-dynamic covariate factors (mental health, substance use and life stress).
Data were available for 962 participants; 6.3% had been exposed to severe sexual abuse and 6.4% to severe physical abuse in childhood. After adjustment for confounding and time-dynamic covariate factors, those exposed to severe sexual abuse had rates of abnormal thought and abnormal perception symptoms that were 2.25 and 4.08 times higher, respectively than the ‘no exposure’ group. There were no significant associations between exposure to severe physical abuse and psychotic experiences.
Findings indicate that exposure to severe childhood sexual (but not physical) abuse is independently associated with an increased risk of psychotic experiences in adulthood (particularly symptoms of abnormal perception) and this association could not be fully accounted for by confounding or time-dynamic covariate factors.
Utilising routine surveillance data, this study presents a method for generating a baseline comparison that can be used in future foodborne outbreak investigations following a case–case methodology. Salmonella and Campylobacter cases (2012–2015) from Maricopa County, AZ were compared to determine differences in risk factors, symptoms and demographics. For foods and other risk factors, adjusted odds ratios were developed using Campylobacter as the reference. Comparisons were also made for three major Salmonella subtypes, Typhimurium, Enteritidis and Poona as compared with Campylobacter. Salmonella cases were younger, while Campylobacter cases were more Hispanic and female. Campylobacter cases reported consuming peppers, sprouts, poultry, queso fresco, eggs and raw nuts more and reported contact with animal products, birds, visiting a farm or dairy, owning a pet, a sick pet, swimming in a river, lake or pond, or handling multiple raw meats more. Salmonella cases reported visiting a petting zoo and contact with a reptile more. There were significant variations by Salmonella subtype in both foods and exposures. We recommend departments conduct this analysis to generate a baseline comparison and a running average of relevant odds ratios allowing staff to focus on trace-back of contaminated food items earlier in the outbreak investigation process.
The Murchison Widefield Array (MWA), located in Western Australia, is one of the low-frequency precursors of the international Square Kilometre Array (SKA) project. In addition to pursuing its own ambitious science programme, it is also a testbed for wide range of future SKA activities ranging from hardware, software to data analysis. The key science programmes for the MWA and SKA require very high dynamic ranges, which challenges calibration and imaging systems. Correct calibration of the instrument and accurate measurements of source flux densities and polarisations require precise characterisation of the telescope’s primary beam. Recent results from the MWA GaLactic Extragalactic All-sky Murchison Widefield Array (GLEAM) survey show that the previously implemented Average Embedded Element (AEE) model still leaves residual polarisations errors of up to 10–20% in Stokes Q. We present a new simulation-based Full Embedded Element (FEE) model which is the most rigorous realisation yet of the MWA’s primary beam model. It enables efficient calculation of the MWA beam response in arbitrary directions without necessity of spatial interpolation. In the new model, every dipole in the MWA tile (4 × 4 bow-tie dipoles) is simulated separately, taking into account all mutual coupling, ground screen, and soil effects, and therefore accounts for the different properties of the individual dipoles within a tile. We have applied the FEE beam model to GLEAM observations at 200–231 MHz and used false Stokes parameter leakage as a metric to compare the models. We have determined that the FEE model reduced the magnitude and declination-dependent behaviour of false polarisation in Stokes Q and V while retaining low levels of false polarisation in Stokes U.
Scrapie is a transmissible spongiform encephalopathy (TSE) and belongs to a category of incurable diseases that include BSE in cattle. An association exists between the Prion-Protein (PrP) genotype of an animal and the risk of developing disease after exposure (Tongue et al., 2004). This PrP genetic information is the basis of the National Scrapie Plan (NSP) which aims, through genotyping, to eradicate those individuals which have the susceptible alleles. Studies into scrapie risk (Jeffrey et al., 2002) have highlighted several alleles which confer scrapie susceptibility. The NSP have used these alleles to categorise individuals according to risk with group one being most scrapie resistant to group five being least resistant. VRQ alleles are synonymous with infection however the ARQ affords susceptibility but not the disease itself. Genotype may however not be the sole indicator of scrapie risk. There is an inference of a relationship between phenotypic characteristics (hornedness, coat colour) and scrapie risk. These alternative indicators of scrapie risk may affect the final choice of susceptible individuals. Scrapie risk studies carried out on the Shetland Isles (Jeffrey et al., 2002) investigated the alleles concerned with scrapie infection. Results confirmed that VRQ alleles are synonymous with scrapie infection however the ARQ alleles, even though they afford susceptibility, do not necessarily confer disease, the animal still has to be exposed to the scrapie agent. Using survey-type questionnaires, the study investigated any potential relationship between the PrP gene, coat colour and hornedness.
Objectives: Medical devices are ubiquitous in modern medical care. However, little is known about the epidemiology of medical devices in the healthcare marketplace, including the rate at which medical devices are subject to recalls or other advisories. We sought to study the epidemiology of medical devices in Canada, focusing on device recalls. In Canada, a recall may signify a variety of events, ranging from relatively minor field safety notifications, to removal of a product from the marketplace.
Methods: We used data from Health Canada to study medical device recalls in Canada from 2005 to 2015. We analyzed the risks of medical device recalls according to the risk class of the device (I lowest; IV highest) and the hazard priority of the recall (Type I highest potential harm; Type III lowest potential harm).
Results: During a 10-year period, there were 7,226 medical device recalls. Most recalls were for intermediate risk class (Class II, 40.1 percent; Class III, 38.7 percent) medical devices. Among recalled devices, 5.0 percent were judged to have a reasonable probability of serious adverse health consequences or death (Type I recall Hazard Priority classification). While the number of medical devices marketed in Canada is not known, over a similar 10-year period, 24,849 new Class II, II, and IV medical device licenses were issued by Health Canada.
Conclusions: Several hundred medical device recalls occur in Canada each year. Further research is needed to characterize the nature of medical device recalls, and to explore how consumers use information about recalls.
The current generation of experiments aiming to detect the neutral hydrogen signal from the Epoch of Reionisation (EoR) is likely to be limited by systematic effects associated with removing foreground sources from target fields. In this paper, we develop a model for the compact foreground sources in one of the target fields of the MWA’s EoR key science experiment: the ‘EoR1’ field. The model is based on both the MWA’s GLEAM survey and GMRT 150 MHz data from the TGSS survey, the latter providing higher angular resolution and better astrometric accuracy for compact sources than is available from the MWA alone. The model contains 5 049 sources, some of which have complicated morphology in MWA data, Fornax A being the most complex. The higher resolution data show that 13% of sources that appear point-like to the MWA have complicated morphology such as double and quad structure, with a typical separation of 33 arcsec. We derive an analytic expression for the error introduced into the EoR two-dimensional power spectrum due to peeling close double sources as single point sources and show that for the measured source properties, the error in the power spectrum is confined to high k⊥ modes that do not affect the overall result for the large-scale cosmological signal of interest. The brightest 10 mis-modelled sources in the field contribute 90% of the power bias in the data, suggesting that it is most critical to improve the models of the brightest sources. With this hybrid model, we reprocess data from the EoR1 field and show a maximum of 8% improved calibration accuracy and a factor of two reduction in residual power in k-space from peeling these sources. Implications for future EoR experiments including the SKA are discussed in relation to the improvements obtained.
Motions of nearby elliptical galaxies reveal a large-scale velocity flow relative to cosmic rest towards the point 1=307±10, b = 9±10. The data are fit best by a two-component flow model. The smaller component is due to Virgo, which induces a velocity at the Local Group of 250 km/s. The main flow is due to a more massive concentration located a distance of 4350±350 km/s towards 1=307, b=9, which induces a local velocity here of 570±60 km/s. This larger component falls off away from the mass concentration roughly as r−1. The Centaurus double cluster and its neighbors are in the direction of the mass concentration but are in the foreground and are falling into it. Galaxy counts, radial velocity surveys, and the motions of nearby spirals are consistent with the above model. The IRAS dipole results are less clear but may also be consistent. There is evidence that the distant mass concentration is non-spherical, with the Centaurus cloud a substantial sub-condensation in the foreground. The formal agreement of the large-scale flow with biased (b=2) cold dark matter is low, but the simple methods used so far to assess this are uncertain. The main weakness of the present data in comparing to theory is the fact that they do not penetrate far enough to show the velocity field on all sides of the mass concentration. Sphericity and total extent of the flow are therefore still unknown.
We analyze the benefits of incorporating climate change into land conservation decisions using wetland migration under rising sea-levels as a case study. We use a simple and inexpensive decision method, a knapsack algorithm implemented in Excel, with (1) simulation data to show that ignoring sea-level rise predictions lead to suboptimal outcomes, and (2) an application to land conservation in Phippsburg, Maine to show the real-world applicability. The simulation shows an 11-percent to almost 30-percent gain in increased benefits when accounting for sea-level rise. The results highlight that it is possible to, and important to, incorporate sea-level rise into conservation planning.
This study uses an experiment where ferry passengers are sold hotel room “views” to evaluate the impact of wind turbines views on tourists’ vacation experience. Participants purchase a chance for a weekend hotel stay. Information about the hotel rooms was limited to the quality of the hotel and its distance from a large wind turbine, as well as whether or not a particular room would have a view of the turbine. While there was generally a negative effect of turbine views, this did not hold across all participants, and did not seem to be effected by distance or hotel quality.
We present low-frequency spectral energy distributions of 60 known radio pulsars observed with the Murchison Widefield Array telescope. We searched the GaLactic and Extragalactic All-sky Murchison Widefield Array survey images for 200-MHz continuum radio emission at the position of all pulsars in the Australia Telescope National Facility (ATNF) pulsar catalogue. For the 60 confirmed detections, we have measured flux densities in 20 × 8 MHz bands between 72 and 231 MHz. We compare our results to existing measurements and show that the Murchison Widefield Array flux densities are in good agreement.
Background: Psychological therapy services are often required to demonstrate their effectiveness and are implementing systematic monitoring of patient progress. A system for measuring patient progress might usefully ‘inform supervision’ and help patients who are not progressing in therapy. Aims: To examine if continuous monitoring of patient progress through the supervision process was more effective in improving patient outcomes compared with giving feedback to therapists alone in routine NHS psychological therapy. Method: Using a stepped wedge randomized controlled design, continuous feedback on patient progress during therapy was given either to the therapist and supervisor to be discussed in clinical supervison (MeMOS condition) or only given to the therapist (S-Sup condition). If a patient failed to progress in the MeMOS condition, an alert was triggered and sent to both the therapist and supervisor. Outcome measures were completed at beginning of therapy, end of therapy and at 6-month follow-up and session-by-session ratings. Results: No differences in clinical outcomes of patients were found between MeMOS and S-Sup conditions. Patients in the MeMOS condition were rated as improving less, and more ill. They received fewer therapy sessions. Conclusions: Most patients failed to improve in therapy at some point. Patients’ recovery was not affected by feeding back outcomes into the supervision process. Therapists rated patients in the S-Sup condition as improving more and being less ill than patients in MeMOS. Those patients in MeMOS had more complex problems.
Two-sided oxidation experiments were recently conducted at 1000-1200°C in flowing steam with samples of sponge-based Zr-1Nb alloy E110. Although the old electrolytic E110 tubing exhibited a high degree of susceptibility to nodular corrosion and experienced breakaway oxidation rates in relatively short time, the new sponge-based E110 has demonstrated steam oxidation behavior comparable to Zircaloy-4. The sponge-based E110 followed the parabolic law, and the derived oxidation rate constant is in good agreement with the Cathcart-Pawel (CP) correlation at 1100-1200°C. For 1000°C oxidation, the weight-gain of sponge-based E110 is much lower than Zircaloy-4. No breakaway oxidation was observed at 1000°C up to 8000 s. Ring compression tests were conducted to evaluate the residual ductility of oxidized samples at room temperature and at 135°C. All sponge-based E110 specimens were still ductile at 135°C after being oxidized up to 20% equivalent cladding reacted at 1000-1200°C. Metallographic examinations were performed on oxidized E110 specimens to correlate material performance with microstructure.
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.
We have used a new distance estimator for elliptical galaxies to determine the peculiar velocities, with respect to a uniform Hubble flow, of approximately 400 galaxies. The relative distances of five clusters in common with those of Aaronson et al. (1981, 1986), based on the infrared Tully-Fisher relation for spirals, are in good agreement.
We do not see the reflex of the Local Group motion with respect to the microwave background out to recession velocities of 6000 km s−1. Rather, the frame of elliptical galaxies appears to be moving with respect to the microwave background with a velocity of 600 km s−1 towards 1 = 312°, b = +6°. This motion is consistent with a re-analysis of the Rubin et al. (1976) data on the magnitude-diameter relation for ScI galaxies and with the nearby and cluster samples of Aaronson et al. (1982, 1986).
We estimate spatial gradients in the ionosphere using the Global Positioning System and GLONASS (Russian global navigation system) observations, utilising data from multiple Global Positioning System stations in the vicinity of Murchison Radio-astronomy Observatory. In previous work, the ionosphere was characterised using a single-station to model the ionosphere as a single layer of fixed height and this was compared with ionospheric data derived from radio astronomy observations obtained from the Murchison Widefield Array. Having made improvements to our data quality (via cycle slip detection and repair) and incorporating data from the GLONASS system, we now present a multi-station approach. These two developments significantly improve our modelling of the ionosphere. We also explore the effects of a variable-height model. We conclude that modelling the small-scale features in the ionosphere that have been observed with the MWA will require a much denser network of Global Navigation Satellite System stations than is currently available at the Murchison Radio-astronomy Observatory.
Background: Health-related quality of life (HRQoL) data is valuable, but limited. This analysis describes the impact of onabotulinumtoxinA treatment on HRQoL and level of treatment satisfaction in cervical dystonia (CD) patients. Methods: A multicenter, prospective, observational study in CD patients initiating onabotulinumtoxinA treatment (NCT01655862); ≤8 treatments administered at the physician’s discretion. Primary measures (baseline, 4/8 weeks post-treatment, and before final treatment): pain numeric rating scale (PNRS) and cervical dystonia impact profile questionnaire (CDIP-58). Secondary measures (8 weeks post-treatment): patient/physician treatment satisfaction. Results: 61 patients (31.3-86.3 years old) were enrolled (efficacy cohort); majority had moderately severe CD (77.0%) and were female (77%). CDIP-58 domain and PNRS scores decreased from baseline, with significant changes (p<.0001) by 4 weeks post-treatment 3 (mean±SD): symptoms (-18.8±16.1), daily activities (-7.2±13.7), psychosocial sequelae (-17.4±13.4), and PNRS (-1.8±3.3). Most patients (78.0% and 94.4%) felt their condition was improved and majority of physicians (68.9% and 75.0%) indicated satisfaction with patients’ responses following treatments 1 and 2, respectively. 27 patients reported 56 treatment-related adverse events (52 resolved, 4 ongoing); none were serious. Conclusions: No new safety signals were identified. Patients and physicians appear to be satisfied with onabotulinumtoxinA treatment for CD. Results suggest that onabotulinumtoxinA treatment may help improve HRQoL.
Color-magnitude diagrams reaching from the giant branches to Vlim ~ 27.0, or about three magnitudes fainter than the turnoff, have been obtained in V and I with WFPC2 on HST for NGC 2419, Pal 3, Pal 4 and Eridanus, whose relative ages are discussed.