We present Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of a massive galaxy cluster discovered in the Arcminute Microkelvin Imager (AMI) blind Sunyaev-Zel'dovich (SZ) ...survey. Without knowledge of the cluster redshift a Bayesian analysis of the AMI, CARMA and joint AMI and CARMA uv-data is used to quantify the detection significance and parametrize both the physical and observational properties of the cluster whilst accounting for the statistics of primary cosmic microwave background anisotropies, receiver noise and radio sources. The joint analysis of the AMI and CARMA uv-data was performed with two parametric physical cluster models: the β-model; and the model described in Olamaie et al. with the pressure profile fixed according to Arnaud et al. The cluster mass derived from these different models is comparable but our Bayesian evidences indicate a preference for the β-profile which we, therefore, use throughout our analysis. From the CARMA data alone we obtain a formal Bayesian probability of detection ratio of 12.8:1 when assuming that a cluster exists within our search area; alternatively assuming that Jenkins et al. accurately predict the number of clusters as a function of mass and redshift, the formal Bayesian probability of detection is 0.29:1. From the Bayesian analysis of the AMI or AMI and CARMA data the probability of detection ratio exceeds 4.5 × 103:1. Performing a joint analysis of the AMI and CARMA data with a physical cluster model we derive the total mass internal to r
200 as M
T, 200 = 4.1 ± 1.1 × 1014 M. Using a phenomenological β-model to quantify the temperature decrement as a function of angular distance we find a central SZ temperature decrement of 170 ± 24 μK in the AMI and CARMA data. The SZ decrement in the CARMA data is weaker than expected and we speculate that this is a consequence of the cluster morphology. In a forthcoming study the pipeline that we have developed for the analyses of these data will be used to thoroughly assess the impact of cluster morphology on the SZ decrements that are observed with interferometers such as AMI and CARMA.
Hypertension accounts for the greatest burden of disease worldwide, yet hypertension awareness and control rates are suboptimal, especially within low- and middle-income countries. Guidelines can ...enable consistency of care and improve health outcomes. A small body of studies investigating clinicians' perceptions and implementation of hypertension guidelines exists, mostly focussed on higher income settings. This study aims to explore how hypertension guidelines are used by clinicians across different resource settings, and the factors influencing their use.
A qualitative approach was employed using convenience sampling and in-depth semi-structured interviews. Seventeen medical doctors were interviewed over video or telephone call from March to August 2020. Two clinicians worked in low-income countries, ten in middle-income countries, and five in high-income countries. Interviews were recorded, transcribed, and coded inductively. Reflexive thematic analysis was used.
Themes were generated at three levels at which clinicians perceived influencing factors to be operating: healthcare worker, healthcare worker interactions with patients, and the wider health system. Within each level, influencing factors were described as barriers to and facilitators of guideline use. Variation in factors occurred across income settings. At the healthcare worker level, usability of guidelines, trust in guidelines, attitudes and views about guidelines' purpose, and relevance to patient populations were identified as themes. Influencing factors at the health system level were accessibility of equipment and medications, workforce, and access to healthcare settings. Influences at the patient level were clinician perceived patient motivation and health literacy, and access to, and cost of treatment, although these represented doctors' perceptions rather than patient perceived factors.
This study adds a high level global view to previous studies investigating clinician perspectives on hypertension guideline use. Guidelines should be evidence-based, regularly updated and attention should be given to increasing applicability to LMICs and a range of healthcare professionals.
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CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT We present 13.9-18.2GHz observations of the Sunyaev-Zel'dovich (SZ) effect towards Abell2146 using the Arcminute Microkelvin Imager (AMI). The cluster is detected with a peak signal-to-noise ...ratio of 13σ in the radio source subtracted map from 9h of data. Comparison of the SZ image with the X-ray image from Russell et al. suggests that both have extended regions which lie approximately perpendicular to one another, with their emission peaks significantly displaced. These features indicate non-uniformities in the distributions of the gas temperature and pressure, and suggest complex dynamics indicative of a cluster merger. We use a fast, Bayesian cluster analysis to explore the high-dimensional parameter space of the cluster-plus-sources model to obtain robust cluster parameter estimates in the presence of radio point sources, receiver noise and primordial cosmic microwave background (CMB) anisotropy; despite the substantial radio emission from the direction of Abell2146, the probability of SZ + CMB primordial structure + radio sources + receiver noise to CMB + radio sources + receiver noise is 3 × 106:1. We compare the results from three different cluster models. Our preferred model exploits the observation that the gas fractions do not appear to vary greatly between clusters. Given the relative masses of the two merging systems in Abell2146, the mean gas temperature can be deduced from the virial theorem (assuming all of the kinetic energy is in the form of internal gas energy) without being affected significantly by the merger event, provided the primary cluster was virialized before the merger. In this model we fit a simple spherical isothermal β-model to our data, despite the inadequacy of this model for a merging system like Abell2146, and assume the cluster follows the mass-temperature relation of a virialized, singular, isothermal sphere. We note that this model avoids inferring large-scale cluster parameters internal to r200 under the widely used assumption of hydrostatic equilibrium. We find that at r200 the average total mass MT= (4.1 ± 0.5) × 1014h-1M and the mean gas temperature T= 4.5 ± 0.5keV. PUBLICATION ABSTRACT
We have obtained deep Sunyaev-Zel'dovich (SZ) observations towards 15 of the hottest XMM Cluster Survey (XCS) clusters that can be observed with the Arcminute Microkelvin Imager (AMI). We use a ...Bayesian analysis to quantify the significance of our SZ detections. We detect the SZ effect at high significance towards three of the clusters and at lower significance for a further two clusters. Towards the remaining 10 clusters, no clear SZ signal was measured. We derive cluster parameters using the XCS mass estimates as a prior in our Bayesian analysis. For all AMI-detected clusters, we calculate large-scale mass and temperature estimates while for all undetected clusters we determine upper limits on these parameters. We find that the large-scale mean temperatures derived from our AMI SZ measurements (and the upper limits from null detections) are substantially lower than the XCS-based core-temperature estimates. For clusters detected in the SZ, the mean temperature is, on average, a factor of 1.4 lower than temperatures from the XCS. Our upper limits on the cluster temperature of undetected systems are lower than the mean XCS derived temperature.
We report new cm-wave measurements at five frequencies between 15 and 18GHz of the continuum emission from the reportedly anomalous ‘region 4’ of the nearby galaxy NGC6946. We find that the emission ...in this frequency range is significantly in excess of that measured at 8.5GHz, but has a spectrum from 15 to 18GHz consistent with optically thin free–free emission from an ultracompact Hii region. In combination with previously published data, we fit four emission models containing different continuum components using the Bayesian spectrum analysis package radiospec. These fits show that, in combination with data at other frequencies, a model with a spinning dust component is slightly preferred to those that possess better-established emission mechanisms.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
La consulta de enfermería de Enfermedad Renal Cróni-ca Avanzada (ERCA) constituye un escenario especialmente complejo(1,2) tanto para el paciente como para los profesionales. Por este motivo, y con ...el objetivo principal de ofrecer apoyo al personal de enfermería durante estas consultas, en la Unidad de ERCA del Servicio de Nefrología del Hospital Universitario La Paz, se en-cuentra dentro del protocolo de actuación la posibilidad de que el psicólogo este físicamente presente en esta consulta. Esta modalidad de actuación está en línea con la evidencia de que un equipo interdisciplinar es necesario para mejorar la comprensión de la enfermedad renal, y con ello la calidad de vida relacionada con la salud (CVRS) de los pacientes con ERCA(3). Este protocolo ha sido publicado como carta al director en la revista Nefrología(4), aunque en la presente versión hacemos énfasis en aspectos diferenciales, principalmente en las funciones específi cas de la enfermería en la consulta de ERCA y la defi nición del perfi l de paciente ante el cual activar este protocolo. El objetivo de promover la difusión del mismo en las distintas sociedades científicas de la especialidad es recordarnos que en el abordaje integral del enfermo renal es mucho más lo que nos une que lo que nos separa.
For medications with low lipid solubility where doses are calculated by the total body weight (TBW) of the child, increasing adiposity may lead to the administration of doses well in excess of that ...required for therapeutic effect, and potentially beyond the safe therapeutic interval of the medication. There are numerous alternative bodyweight scalars which are used in obese children, including ideal body weight (IBW), lean body mass and adjusted body weight.1 IBW is probably the most commonly used in obesity and is the only alternative to TBW mentioned in the British National Formulary for Children.2 There is little consensus on how best to calculate IBW however, and we have previously shown that there is significant discrepancy in the proportion of TBW represented by IBW depending on which of five published methods (Traub, Moore, body mass index (BMI) method, American Dietetic Association, McLaren) is chosen.3 A 2016 study by Collier et al 4 found that there was a generally poor understanding of when and how to calculate IBW in a cohort of UK-based paediatricians. Competing interests The Helix Centre at Imperial College London (within the Department of Surgery and Cancer) is leading an effort in collaboration with the British National Formulary developing digital tools in an attempt to improve paediatric medication safety.
We present 25 arcsec resolution radio images of five Lynds Dark Nebulae (L675, L944, L1103, L1111 and L1246) at 16 GHz made with the Arcminute Microkelvin Imager (AMI) Large Array. These objects were ...previously observed with the AMI Small Array to have an excess of emission at microwave frequencies relative to lower frequency radio data. In L675, we find a flat spectrum compact radio counterpart to the 850 μm emission seen with Submillimetre Common-User Bolometer Array (SCUBA) and suggest that it is cm-wave emission from a previously unknown deeply embedded young protostar. In the case of L1246, the cm-wave emission is spatially correlated with 8 μm emission seen with Spitzer. Since the mid-infrared emission is present only in Spitzer band 4 we suggest that it arises from a population of polycyclic aromatic hydrocarbon molecules, which also give rise to the cm-wave emission through spinning dust emission.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We present results from follow-up observations of a sample of 80 radio sources, originally detected as part of the 15.2-GHz Ninth Cambridge (9C) survey. The observations were carried out, close to ...simultaneously, at two frequencies: 15.7 GHz, using the Arcminute Microkelvin Imager (AMI) Large Array, and 93.2 GHz, using the Combined Array for Research in Millimeter-wave Astronomy (CARMA).
There is currently little direct information on the 90-GHz-band source count for S 1 Jy. However, we have used the measured 15.7-to-93.2-GHz spectral-index distribution and 9C source count to predict the differential source count at 93.2 GHz as 26 ± 4(S/Jy)−2.15 Jy−1 sr−1; our projection is estimated to be most accurate for 10 S 100 mJy.
Our estimated differential count is more than twice the 90-GHz prediction made by Waldram et al.; we believe that this discrepancy is because the measured 43-GHz flux densities used in making their prediction were too low. Similarly, our prediction is significantly higher than that of Sadler et al. at 95 GHz. Since our spectral-index distribution is similar to the 20-to-95-GHz distribution measured by Sadler et al. and used in making their prediction, we believe that the difference is almost entirely attributable to the dissimilarity in the lower frequency counts used in making the estimates.
The Planck Early Release Compact Source Catalogue includes 26 sources with no obvious matches in other radio catalogues (of predominantly extragalactic sources). Here we present observations made ...with the Arcminute Microkelvin Imager Small Array (AMI SA) at 15.75GHz of the eight unmatched sources at delta > +10 degree . Of the eight, four are detected and are associated with known objects. The other four are not detected with the AMI SA, and are thought to be spurious.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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