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We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Journals use social media to increase the awareness of their publications. Infographics show research findings in a concise and visually appealing manner, well suited for dissemination on social media platforms. We hypothesized that infographic abstracts promoted on social media would increase the dissemination and online readership of the parent research articles.
Twenty-four articles were chosen from the six issues of CJEM published between July 2016 and June 2017 and randomized to infographic or control groups. All articles were disseminated through the journal’s social media accounts (Twitter and Facebook). Control articles were promoted using a screen capture image of each article’s abstract on the journal’s social media accounts. Infographic articles were promoted similarly using a visual infographic. Infographics were also published and promoted on the CanadiEM.org’s website and social media channels. Abstract views, full-text views, and the change in Altmetric score were compared between groups using unpaired two-tailed t-tests.
There were no significant differences in the groups at baseline. Abstract views (mean, 95% CI) were higher in the infographics (379, 287-471) than the control group (176, 136-215, p<0.001). Mean change in Altmetric scores was higher in the infographics (26, 18-34) than in the control group (3, 2-4, p<0.0001). There was no difference in full-text views between the infographics (50, 0-101) and control groups (25, 18-32).
The promotion of CJEM articles using infographics on social media and the CanadiEM.org website increased Altmetric scores and abstract views. Infographics may have a role in increasing awareness of medical literature.
Aeroacoustic measurements and analysis have been made for an unshrouded rotor partially immersed in a planar equilibrium turbulent boundary layer at low Mach number. This configuration provides an idealized model of inflow distortion effects seen when a rotor is mounted adjacent to the hull or fuselage of a vehicle. At low and moderate thrust conditions, the rotor produces broadband noise organized into haystacks produced by large eddies of the ingested turbulence being cut multiple times by successive rotor blades. At high thrust, however, the acoustic signature changes and becomes louder and more tonal. This change is accompanied by separation of the boundary layer from the wall in the vicinity of the rotor blade disk. The separation region is highly unsteady and populated by intense vortex structures. Acoustic analysis suggests that blade–vortex interactions with these structures are the source of the additional tonal noise at high thrust.
There is no consensus as to whether magnetic resonance imaging (MRI) should be used as part of the initial clinical evaluation of patients with first-episode psychosis (FEP).
(a) To assess the logistical feasibility of routine MRI; (b) to define the clinical significance of radiological abnormalities in patients with FEP.
Radiological reports from MRI scans of two FEP samples were reviewed; one comprised 108 patients and 98 healthy controls recruited to a research study and the other comprised 241 patients scanned at initial clinical presentation plus 66 healthy controls.
In the great majority of patients, MRI was logistically feasible. Radiological abnormalities were reported in 6% of the research sample and in 15% of the clinical sample (odds ratio (OR) = 3.1, 95% CI 1.26–7.57, χ2(1) = 6.63, P = 0.01). None of the findings necessitated a change in clinical management.
Rates of neuroradiological abnormalities in FEP are likely to be underestimated in research samples that often exclude patients with organic abnormalities. However, the majority of findings do not require intervention.
In 2015 and 2016, the Canadian Journal of Emergency Medicine (CJEM) Social Media (SoMe) Team collaborated with established medical websites to promote CJEM articles using podcasts and infographics while tracking dissemination and readership.
CJEM publications in the “Original Research” and “State of the Art” sections were selected by the SoMe Team for podcast and infographic promotion based on their perceived interest to emergency physicians. A control group was composed retrospectively of articles from the 2015 and 2016 issues with the highest Altmetric score that received standard Facebook and Twitter promotions. Studies on SoMe topics were excluded. Dissemination was quantified by January 1, 2017 Altmetric scores. Readership was measured by abstract and full-text views over a 3-month period. The number needed to view (NNV) was calculated by dividing abstract views by full-text views.
Twenty-nine of 88 articles that met inclusion were included in the podcast (6), infographic (11), and control (12) groups. Descriptive statistics (mean, 95% confidence interval) were calculated for podcast (Altmetric: 61, 42-80; Abstract: 1795, 1135-2455; Full-text: 431, 0-1031), infographic (Altmetric: 31.5, 19-43; Abstract: 590, 361-819; Full-text: 65, 33-98), and control (Altmetric: 12, 8-15; Abstract: 257, 159-354; Full-Text: 73, 38-109) articles. The NNV was 4.2 for podcast, 9.0 for infographic, and 3.5 for control articles.
Limitations included selection bias, the influence of SoMe promotion on the Altmetric scores, and a lack of generalizability to other journals.
Collaboration with established SoMe websites using podcasts and infographics was associated with increased Altmetric scores and abstract views but not full-text article views.
ABSTRACT.This contribution examines rapid developments in naval warfare technology in the Mediterranean world in fourth and third centuries BC, particularly the evolution of large oared warships, known as ‘polyremes’ and the creation of naval siege units for assaults on coastal strongholds by the successors of Alexander the Great. It also explains how unsustainable costs and changing strategic priorities led to their abandonment and the introduction of more cost-effective and adaptable vessels and strategies.
RÉSUMÉ.Cette contribution étudie le rapide développement de la technologie des navires de guerre dans le monde méditerranéen des IVe et IIIe siècles av. J.-C., en particulier l'évolution des grands vaisseaux de guerre à rames connus sous le nom de « polyrèmes », et la création d'appareils dédiés au siège maritime pour l'assaut des bastions côtiers par les successeurs d'Alexandre le Grand. Elle explique également comment les coûts insoutenables et les changements de priorités stratégiques ont conduit à leur abandon et à l'apparition de tactiques et de vaisseaux plus rentables et mieux adaptés.
During the last four centuries BC, naval warfare experienced an incredible burst of technological innovation in both the eastern and western Mediterranean. In the span of roughly a century and a half – from approximately 400 to 250 – warships grew in size from triremes or ‘threes’ to ‘thirties,’ became broader and heavier, and were armed at the bows with bronze rams of increasing size and weight. The numbers contained in the names describing these new galleys (triērēs = ‘three,’ tetrērēs = ‘four,’ triakontērēs = ‘thirty’) relate to their oar systems, with vessels from the same class having roughly similar dimensions and designs. While we are ignorant of the basic specifications of most classes larger than ‘fives,’ we suspect they were powered by crews of many hundreds, even thousands of men, arrayed at one, two, or three levels, with multiple men to an oar. As a whole, we refer to the vessels that were larger than ‘threes’ as ‘polyremes,’ although the ancients preferred to call such warships ‘cataphract’ (kataphraktos) or ‘fenced-in’ from the rowers’ safe placement below the fighting deck. Indeed, the Latin term for such galleys was tectae or ‘decked.’
Very preterm birth (VPT; <32 weeks of gestation) has been associated with impairments in emotion regulation, social competence and communicative skills. However, the neuroanatomical mechanisms underlying such impairments have not been systematically studied. Here we investigated the functional integrity of the amygdala connectivity network in relation to the ability to recognize emotions from facial expressions in VPT adults.
Thirty-six VPT-born adults and 38 age-matched controls were scanned at rest in a 3-T MRI scanner. Resting-state functional connectivity (rs-fc) was assessed with SPM8. A seed-based analysis focusing on three amygdalar subregions (centro-medial/latero-basal/superficial) was performed. Participants’ ability to recognize emotions was assessed using dynamic stimuli of human faces expressing six emotions at different intensities with the Emotion Recognition Task (ERT).
VPT individuals compared to controls showed reduced rs-fc between the superficial subregion of the left amygdala, and the right posterior cingulate cortex (p = 0.017) and the left precuneus (p = 0.002). The VPT group further showed elevated rs-fc between the left superficial amygdala and the superior temporal sulcus (p = 0.008). Performance on the ERT showed that the VPT group was less able than controls to recognize anger at low levels of intensity. Anger scores were significantly associated with rs-fc between the superficial amygdala and the posterior cingulate cortex in controls but not in VPT individuals.
These findings suggest that alterations in rs-fc between the amygdala, parietal and temporal cortices could represent the mechanism linking VPT birth and deficits in emotion processing.
To estimate the folate status of New Zealand women of childbearing age following the introduction, in 2010, of a new voluntary folic acid fortification of bread programme.
The 2011 Folate and Women’s Health Survey was a cross-sectional survey of women aged 18–44 years carried out in 2011. The survey used a stratified random sampling technique with the Electoral Roll as the sampling frame. Women were asked about consumption of folic-acid-fortified breads and breakfast cereals in a telephone interview. During a clinic visit, blood was collected for serum and erythrocyte folate measurement by microbiological assay.
A North Island (Wellington) and South Island (Dunedin) city centre in New Zealand.
Two hundred and eighty-eight women, of whom 278 completed a clinic visit.
Geometric mean serum and erythrocyte folate concentrations were 30 nmol/l and 996 nmol/l, respectively. Folate status was 30–40 % higher compared with women of childbearing age sampled as part of a national survey in 2008/09, prior to the introduction of the voluntary folic acid bread fortification programme. In the 2011 Folate and Women’s Health Survey, reported consumption of fortified bread and fortified breakfast cereal in the past week was associated with 25 % (P=0·01) and 15 % (P=0·04) higher serum folate concentrations, respectively.
Serum and erythrocyte folate concentrations have increased in New Zealand women of childbearing age since the number of folic-acid-fortified breads was increased voluntarily in 2010. Consumption of fortified breads and breakfast cereals was associated with a higher folate status.
This experiment was conducted to determine the effects of diets supplemented with cottonseed oil, Acacia mearnsii-condensed tannin extract, and a combination of both on composition of bovine milk. Treatment diets included addition of cottonseed oil (800 g/d; CSO), condensed tannin from Acacia mearnsii (400 g/d; TAN) or a combination of cottonseed oil (800 g/d) and condensed tannin (400 g/d; CPT) with a diet consisting of 6·0 kg dry matter (DM) of concentrates and alfalfa hay ad libitum, which also served as the control diet (CON). Relative to the CON diet, feeding CSO and CPT diets had a minor impact on feed intake and yield of lactose in milk. These diets increased yields of milk and protein in milk. In contrast to the TAN diet, the CSO and CPT diets significantly decreased milk fat concentration and altered milk fatty acid composition by decreasing the proportion of saturated fatty acids but increasing proportions of monounsaturated and polyunsaturated fatty acids. The CPT diet had a similar effect to the CSO diet in modifying fatty acid profile. Overall, reduction in milk fat concentration and changes in milk fatty acid profile were probably due to supplementation of linoleic acid-rich cottonseed oil. The TAN diet had no effect on feed intake, milk yield and milk protein concentration. However, a reduction in the yields of protein and lactose occurred when cows were fed this diet. Supplemented tannin had no significant effect on fat concentration and changes in fatty acid profile in milk. All supplemented diets did not affect protein concentration or composition, nitrogen concentration, or casein to total protein ratio of the resulting milk.
Field emission (FE) measurements are reported from carbon nanotube (CNT) fibers and laser-patterned free standing films fabricated by direct online condensation from a floating catalyst chemical vapor deposition reactor. Fiber and film cathodes showed stable emission in the 1–2 mA current (I) range at maximum cathode temperatures less than 1000 °C; film cathodes show localized heating at the triangular tips and higher maximum temperatures than the fibers. Fowler–Nordheim (FN) analysis indicated a change in the morphology of the emitters with increasing external electrical field (Eext). Fiber cathode I–Eext data are interpreted as FN emission from the fiber tip which is eventually limited by space-charge effects. At higher Eext, FN emission from the fiber sidewall occurs. The single fiber cathode stopped emitting abruptly when field induced self-heating effects became significant. For CNT films, self-heating effects can destroy a portion of the film, but FE can still occur from other areas.
Many mental health service users delay or avoid disclosing their condition to employers because of experience, or anticipation, of discrimination. However, non-disclosure precludes the ability to request ‘reasonable adjustments’. There have been no intervention studies to support decisionmaking about disclosure to an employer.
To determine whether the decision aid has an effect that is sustained beyond its immediate impact; to determine whether a large-scale trial is feasible; and to optimise the designs of a larger trial and of the decision aid.
In this exploratory randomised controlled trial (RCT) in London, participants were randomly assigned to use of a decision aid plus usual care or usual care alone. Follow-up was at 3 months. Primary outcomes were: (a) stage of decision-making; (b) decisional conflict; and (c) employment-related outcomes (trial registration number: NCT01379014).
We recruited 80 participants and interventions were completed for 36 out of 40 in the intervention group; in total 71 participants were followed up. Intention-to-treat analysis showed that reduction in decisional conflict was significantly greater in the intervention group than among controls (mean improvement −22.7 (s.d. = 15.2) v. −11.2 (s.d. = 18.1), P = 0.005). More of the intervention group than controls were in full-time employment at follow-up (P = 0.03).
The observed reduction in decisional conflict regarding disclosure has a number of potential benefits which next need to be tested in a definitive trial.
Educators are at the heart of educational reforms, such as the introduction of mental health promotion initiatives into early childhood education and care (ECEC) settings. Good quality implementation of reforms requires educators to engage in high quality professional learning: If educators have not had opportunities to gain appropriate knowledge and expertise, new initiatives may be poorly implemented and may consequently achieve limited outcomes. This article reports ECEC educators’ perspectives about the impact on their knowledge and practices of the professional education component of the KidsMatter mental health promotion initiative. Educators from 111 ECEC services across Australia contributed a range of types of data, including questionnaires about their knowledge and self-efficacy, feedback about each professional education session, and photo stories about their changed professional practices. Participants indicated that their professional learning led to changed practices in areas such as interpreting children's behaviours, interacting with children, approaching parents, and collaborating with colleagues. Participants’ photo stories illustrate how professional education that focuses on content, active learning, coherence, and collaboration can positively influence knowledge and practices. However, if such gains are to last beyond relatively highly resourced start-up phases of initiatives, professional education needs to integrate with, and draw from, the ongoing availability of other professionals such as guidance and counselling staff, who have complementary knowledge and expertise; be recognised and embedded as a core component of ECEC educators’ roles and their workplace practices; and be culturally and contextually situated. Staff accounts of the impact of their professional learning on their practices can highlight to policy-makers the practical outcomes of strong investments in professional education. Awareness by other professions of the affordances and constraints faced by ECEC educators may contribute to interdisciplinary synergies among the range of professions involved in mental health promotion in educational settings.