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This study characterises the radio luminosity functions (RLFs) for SFGs and AGN using statistical redshift estimation in the absence of comprehensive spectroscopic data. Sensitive radio surveys over large areas detect many sources with faint optical and infrared counterparts, for which redshifts and spectra are unavailable. This challenges our attempt to understand the population of radio sources. Statistical tools are often used to model parameters (such as redshift) as an alternative to observational data. Using the data from GAMA G23 and EMU early science observations, we explore simple statistical techniques to estimate the redshifts in order to measure the RLFs of the G23 radio sources as a whole and for SFGs and AGN separately. Redshifts and AGN/SFG classifications are assigned statistically for those radio sources without spectroscopic data. The calculated RLFs are compared with existing studies, and the results suggest that the RLFs match remarkably well for low redshift galaxies with an optical counterpart. We use a more realistic high redshift distribution to model the redshifts of (most likely) high redshift radio sources and find that the LFs from our approach match well with measured LFs. We also look at strategies to compare the RLFs of radio sources without an optical counterpart to existing studies.
We present the Evolutionary Map of the Universe (EMU) survey conducted with the Australian Square Kilometre Array Pathfinder (ASKAP). EMU aims to deliver the touchstone radio atlas of the southern hemisphere. We introduce EMU and review its science drivers and key science goals, updated and tailored to the current ASKAP five-year survey plan. The development of the survey strategy and planned sky coverage is presented, along with the operational aspects of the survey and associated data analysis, together with a selection of diagnostics demonstrating the imaging quality and data characteristics. We give a general description of the value-added data pipeline and data products before concluding with a discussion of links to other surveys and projects and an outline of EMU’s legacy value.
We introduce a new approach to quantifying dust in galaxies by combining information from the Balmer decrement (BD) and the dust mass (Md). While there is no explicit correlation between these two properties, they jointly probe different aspects of the dust present in galaxies. We explore two new parameters that link BD with Md by using star formation rate sensitive luminosities at several wavelengths (ultraviolet, Hα, and far-infrared). This analysis shows that combining the BD and Md in these ways provides new metrics that are sensitive to the degree of optically thick dust affecting the short wavelength emission. We show how these new “dust geometry” parameters vary as a function of galaxy mass, star formation rate, and specific star formation rate. We demonstrate that they are sensitive probes of the dust geometry in galaxies, and that they support the “maximal foreground screen” model for dust in starburst galaxies.
We present a novel scheme for rapid quantitative analysis of debris generated during experiments with solid targets following relativistic laser–plasma interaction at high-power laser facilities. Results are supported by standard analysis techniques. Experimental data indicate that predictions by available modelling for non-mass-limited targets are reasonable, with debris of the order of hundreds of μg per shot. We detect for the first time two clearly distinct types of debris emitted from the same interaction. A fraction of the debris is ejected directionally, following the target normal (rear and interaction side). The directional debris ejection towards the interaction side is larger than on the side of the target rear. The second type of debris is characterized by a more spherically uniform ejection, albeit with a small asymmetry that favours ejection towards the target rear side.
Antimicrobial resistance (AMR) renders many bacterial infections untreatable and results in substantial morbidity and mortality worldwide. Understanding antibiotic use in clinical settings including hospitals is critical to optimize antibiotic use and prevent resistance.
Design:
Hospital antibiotic point prevalence survey (PPS).
Methods:
The study was conducted in two large, teaching hospitals in Addis Ababa, Ethiopia. We performed two survey rounds in December 2021 and January 2022 through real-time chart review using the World Health Organization PPS methodology. Data were collected using a web-based database, and descriptive statistics were performed to analyze antibiotic use by various characteristics.
Results:
Among 1020 hospitalized patients, 318 (32%) were ≤14 years and 370 (36%) had surgery during the current hospitalization. A total of 662 (65%) were receiving an antibiotic on the day of survey and 346 (39%) were receiving ≥2 antibiotics. A community-acquired infection (43%) was the most common indication for an antibiotic followed by surgical prophylaxis (27%) and hospital-acquired infection (23%). Antibiotic use was highest among those ≤24 months in age and among patients in trauma, surgical, and pediatric wards. Cephalosporin (42%) and penicillin (16%) antibiotics were the most frequently prescribed classes. Only 11% of patients on antibiotics had samples collected for microbiological testing; hence, almost all antibiotic therapy was empiric.
Conclusions:
Despite global and national efforts to improve antimicrobial stewardship, antibiotic use remains high in urban teaching hospitals in Ethiopia. Implementation of antimicrobial stewardship activities and microbiology utilization are needed to guide antimicrobial selection and curtail antibiotic overuse.
Recent advances in clinical prediction for diarrhoeal aetiology in low- and middle-income countries have revealed that the addition of weather data to clinical data improves predictive performance. However, the optimal source of weather data remains unclear. We aim to compare the use of model estimated satellite- and ground-based observational data with weather station directly observed data for the prediction of aetiology of diarrhoea. We used clinical and etiological data from a large multi-centre study of children with moderate to severe diarrhoea cases to compare their predictive performances. We show that the two sources of weather conditions perform similarly in most locations. We conclude that while model estimated data is a viable, scalable tool for public health interventions and disease prediction, given its ease of access, directly observed weather station data is likely adequate for the prediction of diarrhoeal aetiology in children in low- and middle-income countries.
Hepatitis E virus (HEV) is a major cause of acute jaundice in South Asia. Gaps in our understanding of transmission are driven by non-specific symptoms and scarcity of diagnostics, impeding rational control strategies. In this context, serological data can provide important proxy measures of infection. We enrolled a population-representative serological cohort of 2,337 individuals in Sitakunda, Bangladesh. We estimated the annual risks of HEV infection and seroreversion both using serostatus changes between paired serum samples collected 9 months apart, and by fitting catalytic models to the age-stratified cross-sectional seroprevalence. At baseline, 15% (95 CI: 14–17%) of people were seropositive, with seroprevalence highest in the relatively urban south. During the study, 27 individuals seroreverted (annual seroreversion risk: 15%, 95 CI: 10–21%), and 38 seroconverted (annual infection risk: 3%, 95CI: 2–5%). Relying on cross-sectional seroprevalence data alone, and ignoring seroreversion, underestimated the annual infection risk five-fold (0.6%, 95 CrI: 0.5–0.6%). When we accounted for the observed seroreversion in a reversible catalytic model, infection risk was more consistent with measured seroincidence. Our results quantify HEV infection risk in Sitakunda and highlight the importance of accounting for seroreversion when estimating infection incidence from cross-sectional seroprevalence data.
We propose a new method for identifying active galactic nuclei (AGN) in low mass ($\mathrm{M}_*\leq10^{10}\mathrm{M}_\odot$) galaxies. This method relies on spectral energy distribution (SED) fitting to identify galaxies whose radio flux density has an excess over that expected from star formation alone. Combining data in the Galaxy and Mass Assembly (GAMA) G23 region from GAMA, Evolutionary Map of the Universe (EMU) early science observations, and Wide-field Infrared Survey Explorer (WISE), we compare this technique with a selection of different AGN diagnostics to explore the similarities and differences in AGN classification. We find that diagnostics based on optical and near-infrared criteria (the standard BPT diagram, the WISE colour criterion, and the mass-excitation, or MEx diagram) tend to favour detection of AGN in high mass, high luminosity systems, while the “ProSpect” SED fitting tool can identify AGN efficiently in low mass systems. We investigate an explanation for this result in the context of proportionally lower mass black holes in lower mass galaxies compared to higher mass galaxies and differing proportions of emission from AGN and star formation dominating the light at optical and infrared wavelengths as a function of galaxy stellar mass. We conclude that SED-derived AGN classification is an efficient approach to identify low mass hosts with low radio luminosity AGN.
The Jurassic trigoniid bivalves of Gebel Maghara, northern Sinai, Egypt are described and figured. They belong to 14 species, nine genera, and two families. The identified taxa occur in rocks ranging in age from the Toarcian (Lower Jurassic) to the lower Kimmeridgian (Upper Jurassic). Five genera and one species are new: Magharitrigonia asymmetrica new genus new species; Cotswoldella aff. C. hemisphaerica (Lycett, 1853); Cornbrashella pullus (J. de C. Sowerby, 1826); Parorthotrigonia lepidomorpha (Abdallah and Fahmy, 1969); and Retetrigonia imbricata (J. de C. Sowerby, 1826). Five species, Trigonia reticulata Agassiz, 1840, T. cf. T. castor d'Orbigny, 1849, Promyophorella tuberculata (Agassiz, 1840), Orthotrigonia exortiva (Kitchin, 1903), and O. gracilis (Kitchin, 1903) are recorded from the Jurassic rocks of Gebel Maghara for the first time.
We demonstrate the importance of radio selection in probing heavily obscured galaxy populations. We combine Evolutionary Map of the Universe (EMU) Early Science data in the Galaxy and Mass Assembly (GAMA) G23 field with the GAMA data, providing optical photometry and spectral line measurements, together with Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry, providing IR luminosities and colours. We investigate the degree of obscuration in star-forming galaxies, based on the Balmer decrement (BD), and explore how this trend varies, over a redshift range of $0<z<0.345$. We demonstrate that the radio-detected population has on average higher levels of obscuration than the parent optical sample, arising through missing the lowest BD and lowest mass galaxies, which are also the lower star formation rate (SFR) and metallicity systems. We discuss possible explanations for this result, including speculation around whether it might arise from steeper stellar initial mass functions in low mass, low SFR galaxies.
Scholars recognize the important role that diasporas play in conflict dynamics, including efforts to build peace in conflict-affected communities. Broader academic research emphasizes a focus on local conditions and actors, as well as site-specific understandings of peace and peacebuilding practices. This focus on specific communities and contexts often draws on qualitative, narrative-driven data, predominantly collected through interviewing. This article identifies some of the core challenges related to data collection encountered during semi-structured interviews in a study of Somali diaspora members in Melbourne, Australia. We emphasize how issues associated with cross-cultural and gendered understandings of concepts related to peacebuilding can affect each stage of a research project, from the preliminary collection of data to the analysis and discussion of research implications. Specifically, we address challenges related to instances of conceptual dissonance that occur when researchers employ cross-cultural and gendered concepts—in this case, peace, peacebuilding, and leadership. The findings will benefit conflict researchers who work with socially distant groups and ethnically divided populations more broadly, along with those who employ interpretivist methodologies that focus on how meaning making might ultimately influence peacebuilding practices and outcomes.
Initial specimen diversion devices (ISDDs) are a potential solution for reducing blood-culture contamination rates. We report the implementation of an ISDD associated with a sustained reduction in blood-culture contamination rates for >18 months after implementation. We did not observe a clinically significant reduction in inpatient vancomycin usage.
Up to 90% of adults with untreated atrial septal defect will be symptomatic by 4th decade, and 30-49% will develop heart failure. 8–10% of these patients have pulmonary arterial hypertension with a female predominance regardless of age. We aimed to demonstrate that fenestrated closure can be safely performed in patients with decompensated heart failure and atrial septal defect-associated pulmonary arterial hypertension with improved outcome.
Methods:
Transcatheter fenestrated atrial septal defect closures (Occlutech GmbH, Jena, Germany) were performed on a compassionate-use basis in 5 consecutive adult patients with atrial septal defect-associated pulmonary arterial hypertension and severe heart failure with prohibitive surgical mortality risks. Change in systemic oxygen saturation, 6-minute walk test, NYHA class, echocardiographic and haemodynamic parameters were used as parameters of outcome.
Results:
All patients were female, mean age 48.8 ± 13.5 years, followed up for a median of 29 months (max 64 months). Significant improvements observed in the 6-minute walk test, and oxygen saturation comparing day 0 time point to all other follow-up time points data (B = 1.32, SE = 0.28, t (22.7) = -4.77, p = 0.0001); and in the haemodynamic data (including pulmonary vascular resistance and pulmonary pressure) (B = –0.60, SE = 0.22, t (40.2) = 2.74, p = .009). All patients showed improved right ventricular size and function along with NYHA class. There were no procedure-related complications.
Conclusion:
Fenestrated atrial septal defect closure is feasible in adults with decompensated heart failure and atrial septal defect-associated pulmonary arterial hypertension. It results in sustained haemodynamic and functional improvement
The Jurassic rocks of Gebel Maghara, northern Sinai, Egypt, contain a well-preserved and highly diverse macrobenthic fauna, dominated by bivalves. This fauna, particularly bivalves and gastropods, have received little attention in the last 100 years. In an attempt to provide a sound database on the marine bivalve diversity of Egypt during the Jurassic period, a first faunal group, the protobranch bivalves, is reviewed in detail. Sixteen taxa (three of them new), belonging to two orders, five families, and nine genera are systematically described and compared to closely related Jurassic taxa from various locations, particularly in Europe and India. New species are Nuculoma douvillei n. sp., N. sinaiensis n. sp., and Palaeoneilo aegyptiaca n. sp. In addition, Palaeonucula cuneiformis (J. de C. Sowerby), P. muensteri (Goldfuss), Dacryomya diana (d'Orbigny), D. lacryma (J. de. C. Sowerby), and Praesaccella juriana Cox are identified from Jurassic strata of Egypt for the first time. The younger records of the genus Palaeoneilo have not been accepted by some researchers, since almost all exhibit only limited features. The genus occurs with certainty in the Middle Jurassic (Bajocian‒Bathonian) rocks of Egypt, based on well-preserved external and internal characters. Similarly, Dacryomya and Ryderia from Bathonian‒Kimmeridgian rocks of Egypt are younger than previously recorded from other parts of the world. The identified genera have wide geographic ranges and have been reported from different faunal provinces, which suggests that latitudinal climate differences did not influence their distribution pattern to a great extent.
The interaction of relativistically intense lasers with opaque targets represents a highly non-linear, multi-dimensional parameter space. This limits the utility of sequential 1D scanning of experimental parameters for the optimization of secondary radiation, although to-date this has been the accepted methodology due to low data acquisition rates. High repetition-rate (HRR) lasers augmented by machine learning present a valuable opportunity for efficient source optimization. Here, an automated, HRR-compatible system produced high-fidelity parameter scans, revealing the influence of laser intensity on target pre-heating and proton generation. A closed-loop Bayesian optimization of maximum proton energy, through control of the laser wavefront and target position, produced proton beams with equivalent maximum energy to manually optimized laser pulses but using only 60% of the laser energy. This demonstration of automated optimization of laser-driven proton beams is a crucial step towards deeper physical insight and the construction of future radiation sources.
We present the development and characterization of a high-stability, multi-material, multi-thickness tape-drive target for laser-driven acceleration at repetition rates of up to 100 Hz. The tape surface position was measured to be stable on the sub-micrometre scale, compatible with the high-numerical aperture focusing geometries required to achieve relativistic intensity interactions with the pulse energy available in current multi-Hz and near-future higher repetition-rate lasers ($>$kHz). Long-term drift was characterized at 100 Hz demonstrating suitability for operation over extended periods. The target was continuously operated at up to 5 Hz in a recent experiment for 70,000 shots without intervention by the experimental team, with the exception of tape replacement, producing the largest data-set of relativistically intense laser–solid foil measurements to date. This tape drive provides robust targetry for the generation and study of high-repetition-rate ion beams using next-generation high-power laser systems, also enabling wider applications of laser-driven proton sources.
High venous pressures and associated hepatic congestion are important drivers for Fontan-associated liver disease. The prognostic significance of hepatomegaly as a marker of congestion however is not well defined and is further explored in this research study.
Methods:
Fontan patients who have had liver ultrasound scans were identified from the Prince Sultan Cardiac Centre Fontan Database and had their anatomic, surgical, clinical histories abstracted from the electronic medical records following institutional ethics approval. Liver volumes were determined retrospectively from reviewing individual US images, and these, divided into tertiles, were analysed in the context of the predefined endpoints of (i) Primary – death or heart or liver transplantation, or (ii) Secondary – combined endpoint of death, transplantation, arrhythmia, or protein-losing enteropathy.
Results:
Mean indexed liver volumes for the entire cohort (n = 199) were 1065.1 ± 312.1 ml/m2, range 387 to 2071 ml/m2. Patients with the largest liver volumes (highest tertile) were less likely to have a functioning fenestration compared to those in the lowest tertile 44% versus 56% p = 0.016 and experienced the highest burden of mortality and heart or heart–liver transplantation, p = 0.016, and were more likely to reach the composite endpoint of death, protein-losing enteropathy, arrhythmia, or transplantation, p = 0.010. Liver volumes had an overall predictive accuracy for the combined outcome of 61% (CI 53%, 67%, p = 0.009).
Conclusions:
Liver volumetry may serve as a potentially important congestion biomarker for adverse outcomes after the Fontan operation.