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The Murchison Widefield Array is a low-frequency Square Kilometre Array precursor located at the Murchison Radio-astronomy Observatory in Western Australia. Primarily designed as an imaging telescope, but with a flexible signal path, the capabilities of this telescope have recently been extended to include off-line incoherent and tied-array beam formation using recorded antenna voltages. This has provided the capability for high-time and frequency resolution observations, including a pulsar science program. This paper describes the algorithms and pipeline that we have developed to form the tied-array beam products from the summation of calibrated signals of the antenna elements, and presents example polarimetric profiles for PSRs J0437-4715 and J1900-2600 at 185 MHz.
A computerized systetn, consisting of a fluorescence x-ray source (Philips), an Si (Li) detector (Ortec), and a mini Computer (Xerox) is currentiy in operation at The University of Texas M. D. Anderson Hospital and Tumor Institute, Experimentel Pathology Section, for the analysis of trace elements in biological specimens. The elements of interest are Fe, Cu, and Zn for possible significance in the detection and study of cancer. The detection system is being used for comparatively routine analysis of these elements, which are present in blood serum in the ppM range. With appropriate sample preparation techniques, using 1 ml of serum, the limit of detectability for these elements is estimated to be 100 ppB (1 in 107). Further refinement is possible, and research in this direction continues.
Introduction: The ECG diagnosis of acute coronary occlusion (ACO) in the setting of ventricular paced rhythm (VPR) is purported to be impossible. However, VPR has a similar ECG morphology to LBBB. The validated Smith-modified Sgarbossa criteria (MSC) have high sensitivity (Sens) and specificity (Spec) for ACO in LBBB. MSC consist of 1 of the following in 1 lead: concordant ST Elevation (STE) 1 mm, concordant ST depression 1 mm in V1-V3, or ST/S ratio <−0.25 (in leads with 1 mm STE). We hypothesized that the MSC will have higher Sens for diagnosis of ACO in VPR when compared to the original Sgarbossa criteria. We report preliminary findings of the Paced Electrocardiogram Requiring Fast Emergency Coronary Therapy (PERFECT) study Methods: The PERFECT study is a retrospective, multicenter, international investigation of ED patients from 1/2008 - 12/2016 with VPR on the ECG and symptoms suggestive of acute coronary syndrome (e.g. chest pain or shortness of breath). Data from four sites are presented. Acute myocardial infarction (AMI) was defined by the Third Universal Definition of AMI. A blinded cardiologist adjudicated ACO, defined as thrombolysis in myocardial infarction score 0 or 1 on coronary angiography; a pre-defined subgroup of ACO patients with peak cardiac troponin (cTn) >100 times the 99% upper reference limit (URL) of the cTn assay was also analyzed. Another blinded physician measured all ECGs. Statistics were by Mann Whitney U, Chi-square, and McNemars test. Results: The ACO and No-AMI groups consisted of 15 and 79 encounters, respectively. For the ACO and No-AMI groups, median age was 78 [IQR 72-82] vs. 70 [61-75] and 13 (86%) vs. 48 (61%) patients were male. The median peak cTn ratio (cTn/URL) was 260 [33-663] and 0.5 [0-1.3] for ACO vs. no-AMI. The Sens and Spec for the MSC and the original Sgarbossa criteria were 67% (95%CI 39-87) vs. 46% (22-72; p=0.25) and 99% (92-100) vs. 99% (92-100; p=0.5). In pre-defined subgroup analysis of ACO patients with peak cTn >100 times the URL (n=10), the Sens was 90% (54-100) for the MSC vs. 60% (27- 86) for original Sgarbossa criteria (p=0.25). Conclusion: ACO in VPR is an uncommon condition. The MSC showed good Sens for diagnosis of ACO in the presence of VPR, especially among patients with high peak cTn, and Spec was excellent. These methods and results are consistent with studies that have used the MSC to diagnose ACO in LBBB.
Many women experience both vasomotor menopausal symptoms (VMS) and depressed mood at midlife, but little is known regarding the prospective bi-directional relationships between VMS and depressed mood and the role of sleep difficulties in both directions.
A pooled analysis was conducted using data from 21 312 women (median: 50 years, interquartile range 49−51) in eight studies from the InterLACE consortium. The degree of VMS, sleep difficulties, and depressed mood was self-reported and categorised as never, rarely, sometimes, and often (if reporting frequency) or never, mild, moderate, and severe (if reporting severity). Multivariable logistic regression models were used to examine the bi-directional associations adjusted for within-study correlation.
At baseline, the prevalence of VMS (40%, range 13–62%) and depressed mood (26%, 8–41%) varied substantially across studies, and a strong dose-dependent association between VMS and likelihood of depressed mood was found. Over 3 years of follow-up, women with often/severe VMS at baseline were more likely to have subsequent depressed mood compared with those without VMS (odds ratios (OR) 1.56, 1.27–1.92). Women with often/severe depressed mood at baseline were also more likely to have subsequent VMS than those without depressed mood (OR 1.89, 1.47–2.44). With further adjustment for the degree of sleep difficulties at baseline, the OR of having a subsequent depressed mood associated with often/severe VMS was attenuated and no longer significant (OR 1.13, 0.90–1.40). Conversely, often/severe depressed mood remained significantly associated with subsequent VMS (OR 1.80, 1.38–2.34).
Difficulty in sleeping largely explained the relationship between VMS and subsequent depressed mood, but it had little impact on the relationship between depressed mood and subsequent VMS.
The appeal of ketamine – in promptly ameliorating depressive symptoms even in those with non-response – has led to a dramatic increase in its off-label use. Initial promising results await robust corroboration and key questions remain, particularly concerning its long-term administration. It is, therefore, timely to review the opinions of mood disorder experts worldwide pertaining to ketamine's potential as an option for treating depression and provide a synthesis of perspectives – derived from evidence and clinical experience – and to consider strategies for future investigations.
We present techniques developed to calibrate and correct Murchison Widefield Array low-frequency (72–300 MHz) radio observations for polarimetry. The extremely wide field-of-view, excellent instantaneous (u, v)-coverage and sensitivity to degree-scale structure that the Murchison Widefield Array provides enable instrumental calibration, removal of instrumental artefacts, and correction for ionospheric Faraday rotation through imaging techniques. With the demonstrated polarimetric capabilities of the Murchison Widefield Array, we discuss future directions for polarimetric science at low frequencies to answer outstanding questions relating to polarised source counts, source depolarisation, pulsar science, low-mass stars, exoplanets, the nature of the interstellar and intergalactic media, and the solar environment.
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.
A wide range of models have been proposed to account for low-frequency (≲ 1 GHz) variability in cosmologically-distant radio sources. To address these models we (Payne et al. 1982) are monitoring the 0.3–1.4 GHz spectra of such sources. Results from three years of monitoring indicate that two distinct types of low-frequency variables may exist.
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.
The yields of spring barley during a medium-term (7 years) compost and slurry addition experiment and the soil carbon (C) and nitrogen (N) contents, bacterial community structure, soil microbial biomass and soil respiration rates have been determined to assess the effects of repeated, and in some cases very large, organic amendments on soil and crop parameters. For compost, total additions were equivalent to up to 119 t C/ha and 1·7 t N/ha and for slurry they were 25 t C/ha and 0·35 t N/ha over 7 years, which represented very large additions compared to control soil C and N contents (69 t C/ha and 0·3 t N/ha in the 0–30 cm soil depth). There was an initial positive response to compost and slurry addition on barley yield, but over the experiment the yield differential between the amounts of compost addition declined, indicating that repeated addition of compost at a lower rate over several years had the same cumulative effect as a large single compost application. By the end of the experiment it was clear that the addition of compost and slurry increased soil C and N contents, especially towards the top of the soil profile, as well as soil respiration rates. However, the increases in soil C and N contents were not proportional to the amount of C and N added, suggesting either that: (i) a portion of the added C and N was more vulnerable to loss; (ii) that its addition rendered another C or N pool in the soil more susceptible to loss; or (iii) that the C inputs from additional crop productivity did not increase in line with the organic amendments. Soil microbial biomass was depressed at the highest rate of organic amendment, and whilst this may have been due to genuine toxic or inhibitory effects of large amounts of compost, it could also be due to the inaccuracy of the substrate-induced respiration approach used for determining soil biomass when there is a large supply of organic matter. At the highest compost addition, the bacterial community structure was significantly altered, suggesting that the amendments significantly altered soil community dynamics.
We have compiled a catalogue of H ii regions detected with the Murchison Widefield Array between 72 and 231 MHz. The multiple frequency bands provided by the Murchison Widefield Array allow us identify the characteristic spectrum generated by the thermal Bremsstrahlung process in H ii regions. We detect 306 H ii regions between 260° < l < 340° and report on the positions, sizes, peak, integrated flux density, and spectral indices of these H ii regions. By identifying the point at which H ii regions transition from the optically thin to thick regime, we derive the physical properties including the electron density, ionised gas mass, and ionising photon flux, towards 61 H ii regions. This catalogue of H ii regions represents the most extensive and uniform low frequency survey of H ii regions in the Galaxy to date.
The efficacy of three sources of vitamins A and D supplements was tested in an experiment with fattening pigs involving the following four treatments :
(1) Control—basal meal.
(2) As control, but at one week of age the pigs had been given a single intramuscular injection of a commercial preparation, supplying 500,000 i.u. of vitamin A and 100,000 i.u. of vitamin D3.
(3) Basal meal + 1 % cod-liver oil (containing 500 i.u./g. of vitamin A and 68 i.u./g. of vitamin 3), supplying 2,270 i.u. of vitamin A and 309 i.u. of vitamin D3 per lb. of diet.
(4) Basal meal + synthetic vitamins A and D concentrate (containing 50,000 i.u./g. of vitamin A and 5,000 i.u./g. of vitamin D3), added to supply 2,250 i.u. of vitamin A and 300 i.u. of vitamin D3 per lb. of diet.
The basal meal which was the standard fattening diet used at Shinfield consisted of: fine miller’s offal 50, barley meal 30, flaked maize 10, white fish meal 10, all parts by weight. It should be noted that the diet contained a precursor of vitamin A, and it was calculated that this would provide about one-third of the recommended allowance of vitamin A for fattening pigs.
Apathy has been reported as a possible adverse effect of deep brain stimulation of the subthalamic nucleus (STN-DBS). We investigated the prevalence and severity of apathy in 22 patients with Parkinson’s disease (PD) who underwent STN-DBS, as well as the effects of apathy on quality of life (QOL).
All patients were assessed with the Lille Apathy Rating Scale (LARS), the Apathy Scale (AS), and the Parkinson’s Disease Questionnaire and were compared to a control group of 38 patients on pharmacotherapy alone.
There were no significant differences in the prevalence or severity of apathy between patients who had undergone STN-DBS and those on pharmacotherapy alone. Significant correlations were observed between poorer QOL and degree of apathy, as measured by the LARS (p<0.001) and the AS (p=0.021). PD-related disability also correlated with both apathy ratings (p<0.001 and p=0.017, respectively).
Our findings suggest that STN-DBS is not necessarily associated with apathy in the PD population; however, more severe apathy appears to be associated with a higher level of disability due to PD and worse QOL, but no other clinico-demographic characteristics.
It is well-nigh impossible to give, in a short report, an adequate idea of the enormous activity in Variable-Star Astronomy during the past three years. Without attempting to be complete I shall give a summary of the most important recent occurrences in this field of research.
Statistical data for eclipsing binaries were given by Gaposchkin (Veröff. Berlin-Bab. 9, Heft 5), for long-period variable stars by Ludendorff (Sitz.-ber. Ak. d. Wiss. Berlin, 1932), Thomas (Veröff. Berlin-Bab. 9, Heft 4) and Sterne and L. Campbell (Harvard Annals).
Some valuable catalogues have been issued: a Finding List for Observers of Eclipsing Variables by Dugan (Princeton Contr. No. 15), a Catalogue of Eclipsing Variables, together with a Program of Investigations, by Martinoff (Engelhardt Obs. Bull. No. 2), a Catalogue and Ephemeris of Short-period Cepheids by Zessewitsch (Len. Un. A. 0. Bull. No. 3).
The Commission again subscribes to a number of the good resolutions it has made in the past, for example, to follow the almost universal practice of counting the observed times, either in decimals of a day or in hours and minutes, from Greenwich mean noon, even though one is convinced that the rest of the world should adopt U.T.; and to prepare a chart, identifying the variable and the comparison stars, to form a part of the discovery announcement of a variable which cannot be easily identified through a Durchmusterung number and which is bright enough to invite further observation.
Post-traumatic stress disorder (PTSD) is associated with elevated risk for metabolic syndrome (MetS). However, the direction of this association is not yet established, as most prior studies employed cross-sectional designs. The primary goal of this study was to evaluate bidirectional associations between PTSD and MetS using a longitudinal design.
A total of 1355 male and female veterans of the conflicts in Iraq and Afghanistan underwent PTSD diagnostic assessments and their biometric profiles pertaining to MetS were extracted from the electronic medical record at two time points (spanning ~2.5 years, n = 971 at time 2).
The prevalence of MetS among veterans with PTSD was just under 40% at both time points and was significantly greater than that for veterans without PTSD; the prevalence of MetS among those with PTSD was also elevated relative to age-matched population estimates. Cross-lagged panel models revealed that PTSD severity predicted subsequent increases in MetS severity (β = 0.08, p = 0.002), after controlling for initial MetS severity, but MetS did not predict later PTSD symptoms. Logistic regression results suggested that for every 10 PTSD symptoms endorsed at time 1, the odds of a subsequent MetS diagnosis increased by 56%.
Results highlight the substantial cardiometabolic concerns of young veterans with PTSD and raise the possibility that PTSD may predispose individuals to accelerated aging, in part, manifested clinically as MetS. This demonstrates the need to identify those with PTSD at greatest risk for MetS and to develop interventions that improve both conditions.
In an attempt to distill what we know about the effects of workplace mindfulness-based training, Hyland, Lee, and Mills (2015) cast a wide net with regard to the array of studies included in their review. For example, they include studies that investigate the benefits associated with workplace mindfulness training (e.g., Wolever et al., 2012) as well as training conducted for patients within primary care settings (e.g., Allen, Bromley, Kuyken, & Sonnenberg, 2009). In addition, their review includes studies based on self-reports of individual differences in mindfulness traits/skills (e.g., Hafenbrack, Kinias, & Barsade, 2014). Reviewing a broad cross-section of research is helpful to illustrate the wide-ranging nature of mindfulness research but also has the potential to obfuscate what we know about mindfulness as it pertains to workers and workplaces.