•Vulnerability assessments provide the basis for climate adaptation planning.•We assess the vulnerability of 240 cattle producers across Northern Australia.•Vulnerability is assessed using ...sensitivity to change and adaptive capacity.•We found that there were four main types of producers based on their vulnerability.•Only 16% of producers were recognized as not vulnerable to climate change.
Adaptation of agricultural industries to climate change will make a major difference to the extent of the impacts experienced as a result of climate change. Vulnerability assessments provide the basis for developing strategies to reduce social vulnerability and plan for climate adaptation. Primary industries have been identified as the most vulnerable industry sector globally. We review how primary producers might be socially vulnerable to climate change and develop a ‘vulnerability typology’ of cattle producers based on survey responses from 240 producers across northern Australia. We measured social vulnerability according to ten indicators of climate sensitivity (resource dependency) and four indicators of adaptive capacity. Using a K-means clustering analysis we identified four main ‘types’ of cattle producers. Type 1 producers (43%) were vulnerable because they had low strategic skills and low interest in changing behaviour. Mean age was 59 years old, they were weakly networked within the industry and businesses were small. Type II producers (41%) had low strategic skills, poorly managed risk and uncertainty, had medium sized businesses and were 51 years old on average. Only 16% of producers (Type III and IV) appeared to have resilience to change. Type III producers (13.4%) had a stronger psychological and financial buffer, were 52 years old on average, were well networked and managed or owned larger businesses. Type IV producers (2.6%) managed risk well, liked to experiment with options and were interested in change. They were 41 years old on average, managed extremely large properties, were well networked, perceived themselves as responsible for the future productivity of their land and were early adopters of new technology. By providing knowledge of the different ways in which people can be vulnerable to climate change, vulnerability assessments can enable decision-makers to prioritise their efforts, provide a basis for early engagement, and tailor a range of adaptation approaches to most effectively accommodate and support the divergent requirements of different “types” of resource-users.
The XMM-Newton serendipitous survey Rosen, S R; Webb, N A; Watson, M G ...
Astronomy and astrophysics (Berlin),
06/2016, Letnik:
590
Journal Article
Recenzirano
Odprti dostop
Context. Thanks to the large collecting area (3 x~1500 cm super(2) at 1.5 keV) and wide field of view (30' across in full field mode) of the X-ray cameras on board the European Space Agency X-ray ...observatory XMM-Newton, each individual pointing can result in the detection of up to several hundred X-ray sources, most of which are newly discovered objects. Since XMM-Newton has now been in orbit for more than 15 yr, hundreds of thousands of sources have been detected. Aims. Recently, many improvements in the XMM-Newton data reduction algorithms have been made. These include enhanced source characterisation and reduced spurious source detections, refined astrometric precision of sources, greater net sensitivity for source detection, and the extraction of spectra and time series for fainter sources, both with better signal-to-noise. Thanks to these enhancements, the quality of the catalogue products has been much improved over earlier catalogues. Furthermore, almost 50% more observations are in the public domain compared to 2XMMi-DR3, allowing the XMM-Newton Survey Science Centre to produce a much larger and better quality X-ray source catalogue. Methods. The XMM-Newton Survey Science Centre has developed a pipeline to reduce the XMM-Newton data automatically. Using the latest version of this pipeline, along with better calibration, a new version of the catalogue has been produced, using XMM-Newton X-ray observations made public on or before 2013 December 31. Manual screening of all of the X-ray detections ensures the highest data quality. This catalogue is known as 3XMM. Results. In the latest release of the 3XMM catalogue, 3XMM-DR5, there are 565962 X-ray detections comprising 396910 unique X-ray sources. Spectra and lightcurves are provided for the 133000 brightest sources. For all detections, the positions on the sky, a measure of the quality of the detection, and an evaluation of the X-ray variability is provided, along with the fluxes and count rates in 7 X-ray energy bands, the total 0.2-12 keV band counts, and four hardness ratios. With the aim of identifying the detections, a cross correlation with 228 catalogues of sources detected in all wavebands is also provided for each X-ray detection. Conclusions. 3XMM-DR5 is the largest X-ray source catalogue ever produced. Thanks to the large array of data products associated with each detection and each source, it is an excellent resource for finding new and extreme objects.
The majority of ultraluminous X-ray sources are point sources that are spatially offset from the nuclei of nearby galaxies and whose X-ray luminosities exceed the theoretical maximum for spherical ...infall (the Eddington limit) onto stellar-mass black holes. Their X-ray luminosities in the 0.5-10 kiloelectronvolt energy band range from 10(39) to 10(41) ergs per second. Because higher masses imply less extreme ratios of the luminosity to the isotropic Eddington limit, theoretical models have focused on black hole rather than neutron star systems. The most challenging sources to explain are those at the luminous end of the range (more than 10(40) ergs per second), which require black hole masses of 50-100 times the solar value or significant departures from the standard thin disk accretion that powers bright Galactic X-ray binaries, or both. Here we report broadband X-ray observations of the nuclear region of the galaxy M82 that reveal pulsations with an average period of 1.37 seconds and a 2.5-day sinusoidal modulation. The pulsations result from the rotation of a magnetized neutron star, and the modulation arises from its binary orbit. The pulsed flux alone corresponds to an X-ray luminosity in the 3-30 kiloelectronvolt range of 4.9 × 10(39) ergs per second. The pulsating source is spatially coincident with a variable source that can reach an X-ray luminosity in the 0.3-10 kiloelectronvolt range of 1.8 × 10(40) ergs per second. This association implies a luminosity of about 100 times the Eddington limit for a 1.4-solar-mass object, or more than ten times brighter than any known accreting pulsar. This implies that neutron stars may not be rare in the ultraluminous X-ray population, and it challenges physical models for the accretion of matter onto magnetized compact objects.
A new candidate pulsating ULX in NGC 7793 Quintin, E; Webb, N A; Gúrpide, A ...
Monthly notices of the Royal Astronomical Society,
06/2021, Letnik:
503, Številka:
4
Journal Article
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ABSTRACT
We report here the discovery of NGC 7793 ULX-4, a new transient ultraluminous X-ray source (ULX) in NGC 7793, a spiral galaxy already well known for harbouring several ULXs. This new source ...underwent an outburst in 2012, when it was detected by XMM–Newton and the Swift X-ray telescope. The outburst reached a peak luminosity of 3.4 × 1039 erg s−1 and lasted for about eight months, after which the source went below a luminosity of 1037 erg s−1; previous Chandra observations constrain the low-state luminosity below ∼2 × 1036 erg s−1, implying a variability of at least a factor 1000. We propose four possible optical counterparts, found in archival HST observations of the galaxy. A pulsation in the XMM–Newton signal was found at 2.52 Hz, with a significance of $\sim 3.4\, \sigma$, and an associated spin-up of $\dot{f} = 3.5\times 10^{-8}$ Hz s−1. NGC 7793 is therefore the first galaxy to host more than one pulsating ULX.
Diabet. Med. 27, 887–895 (2010)
Aims Risk assessment scores identify those at high risk of impaired glucose regulation and Type 2 diabetes mellitus. To date no risk assessment scores that can be ...completed by a lay person have been developed and validated specifically for multiethnic populations in the UK.
Methods We used data on 6186 subjects aged 40–75 years from a multiethnic UK screening study (73% white European, 22% South Asian). All participants were given a 75 g oral glucose tolerance test. We developed logistic regression models for predicting current impaired glucose regulation (impaired fasting glycaemia/impaired glucose tolerance) or Type 2 diabetes mellitus using data from anthropometric measurements and self‐reported questionnaires. Using the best‐fitting model, we developed the Leicester Risk Assessment score. We externally validated the score using data from 3171 subjects aged 40–75 years from a separate screening study.
Results The components of the final model are age, ethnicity white European vs. other (predominantly South Asian), sex, first degree family history of diabetes, antihypertensive therapy or history of hypertension, waist circumference and body mass index. The score ranges from 0 to 47. Validating this model using the data from the second screening study gave an area under the receiver operator characteristic curve of 72% (95% confidence interval, 69–74%). A cut point of 16 had a sensitivity of 81% and a specificity of 45%.
Conclusions The Leicester Risk Assessment score can be used to identify those at high risk of impaired glucose regulation and Type 2 diabetes mellitus in UK multiethnic populations. The score is simple (seven questions) and non‐invasive.
Context.
The observations carried out with
XMM-Newton
have produced a very extensive X-ray source catalogue in which the standard pipeline determines the variability of sufficiently bright sources ...through
χ
2
and fractional variability tests. Faint sources, however, are not automatically checked for variability, and this means that faint, short timescale transients are overlooked. From dedicated X-ray searches, as well as optical and radio archive searches, we know that some such dim sources can still be identified with high confidence.
Aims.
Our goal is to find new faint, fast transients in
XMM-Newton
EPIC-pn observations. To that end we created the EPIC-pn
XMM-Newton
outburst detector (EXOD) algorithm, which we run on the EPIC-pn full-frame data available in the 3XMM-DR8 catalogue.
Methods.
In EXOD, we computed the variability of the whole field of view by first binning in time the counts detected in each pixel of the detector. We next computed the difference between the median and maximal number of counts in each time bin and pixel to detect variability. We applied EXOD to 5751 observations in the full frame mode and compared the variability of the detected sources to the standard
χ
2
and Kolmogorov–Smirnov (KS) variability tests.
Results.
The algorithm is able to detect periodic and aperiodic variability, with both short and long flares. Of the sources detected by EXOD, 60−95% are also shown to be variable by the standard
χ
2
and KS tests. EXOD computes the variability over the entire field of view faster than the light curve generation takes for all the individual sources. We detect a total of 2961 X-ray variable sources. After removing the spurious detections, we obtain a net number of 2536 variable sources. Of these we investigate the nature of 35 sources with no previously confirmed classification. Amongst the new sources, we find stellar flares and AGNs, in addition to four extragalactic type I X-ray bursters that double the known neutron-star population in M 31.
Conclusions.
This algorithm is a powerful tool for the prompt detection of interesting variable sources in
XMM-Newton
observations. EXOD also detects fast transients that other variability tests would classify as non-variable due to their short duration and low number of counts. This is of increasing importance for the multi-messenger detection of transient sources. Finally, EXOD allows us to identify the nature of compact objects through their variability and to detect rare compact objects. We demonstrate this through the discovery of four extragalactic neutron-star low-mass X-ray binaries, doubling the number of known neutron stars in M 31.
The brightest ultra-luminous X-ray source, ESO 243-49 HLX-1, with a 0.2-10 keV X-ray luminosity of up to 10{sup 42} erg s{sup -1}, provides the strongest evidence to date for the existence of ...intermediate mass black holes (BHs). Although small-scale X-ray spectral variability has already been demonstrated, we have initiated a monitoring campaign with the X-ray Telescope (XRT) onboard the Swift satellite to search for luminosity-related spectral changes and to compare its behavior with the better-studied stellar mass BHs. In this Letter, we report a drop in the XRT count rate by a factor of approx8 which occurred simultaneously with a hardening of the X-ray spectrum. A second observation found that the source had re-brightened by a factor of approx21 which occurred simultaneously with a softening of the X-ray spectrum. This may be the first evidence for a transition between the low/hard and high/soft states.
The public and patients are primary contributors and beneficiaries of pandemic-relevant clinical research. However, their views on research participation during a pandemic have not been ...systematically studied. We aimed to understand public views regarding participation in clinical research during a hypothetical influenza pandemic.
This is an international cross-sectional survey.
We surveyed the views of nationally representative samples of people in Belgium, Poland, Spain, Ireland, the United Kingdom, Canada, Australia and New Zealand, using a scenario-based instrument during the 2017 regional influenza season. Descriptive and regression analyses were conducted.
Of the 6804 respondents, 5572 (81.8%) thought pandemic-relevant research was important, and 5089 (74.8%) thought ‘special rules’ should be applied to make this research feasible. The respondents indicated willingness to take part in lower risk (4715, 69.3%) and higher risk (3585, 52.7%) primary care and lower risk (4780, 70.3%) and higher risk (4113, 60.4%) intensive care unit (ICU) study scenarios. For primary care studies, most (3972, 58.4%) participants preferred standard enrolment procedures such as prospective written informed consent, but 2327 (34.2%) thought simplified procedures would be acceptable. For ICU studies, 2800 (41.2%) preferred deferred consent, and 2623 (38.6%) preferred prospective third-party consent. Greater knowledge about pandemics, trust in a health professional, trust in the government, therapeutic misconception and having had ICU experience as a patient or carer predicted increased willingness to participate in pandemic-relevant research.
Our study indicates current public support for pandemic-relevant clinical research. Tailored information and initiatives to advance research literacy and maintain trust are required to support pandemic-relevant research participation and engagement.
•There is strong public support for pandemic-relevant clinical research initiatives.•Willingness to take part and to sign up under permissive approaches depends on type of research and key participant factors.•Knowledge of pandemics, trust in doctors and government, and experience of critical illness influence research participation.
ABSTRACT
Ultraluminous X-ray sources (ULXs) provide a unique opportunity to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddington ...accretion are not well understood, and so studying correlated variability between different energy bands can provide insights into the causal connection between different emitting regions. We present a spectral-timing analysis of NGC 1313 X-1 from a recent XMM–Newton campaign. The spectra can be decomposed into two thermal-like components, the hotter of which may originate from the inner accretion disc, and the cooler from an optically thick outflow. We find correlated variability between hard (2–10 keV) and soft (0.3–2 keV) bands on kilosecond time-scales, and find a soft lag of ∼150 s. The covariance spectrum suggests that emission contributing to the lags is largely associated with the hotter of the two thermal-like components, likely originating from the inner accretion flow. This is only the third ULX to exhibit soft lags. The lags range over three orders of magnitude in amplitude, but all three are ∼5–20 per cent of the corresponding characteristic variability time-scales. If these soft lags can be understood in the context of a unified picture of ULXs, then lag time-scales may provide constraints on the density and extent of radiatively driven outflows.
Minimizing steroid exposure in pediatric renal transplant recipients can improve linear growth and reduce metabolic disorders. This randomized multicenter study investigated the impact of early ...steroid withdrawal on mean change in height standard deviation score (SDS) and the safety and efficacy of two immunosuppressive regimens during the first 6 months after transplantation. Children received tacrolimus, MMF, two doses of daclizumab and steroids until day 4 (TAC/MMF/DAC, n=98) or tacrolimus, MMF and standard‐dose steroids (TAC/MMF/STR, n=98). Mean change in height SDS was 0.16 ± 0.32 with TAC/MMF/DAC and 0.03 ± 0.32 with TAC/MMF/STR. The mean treatment group difference was 0.13 (p < 0.005 95% CI 0.04–0.22), 0.21 in prepubertal (p = 0.009 95% CI 0.05–0.36) and 0.05 in pubertal children (p = ns). Frequency of biopsy‐proven acute rejection was 10.2%, TAC/MMF/DAC, and 7.1%, TAC/MMF/STR. Patient and graft survival and renal function were similar. Significantly greater reductions in total cholesterol and triglycerides but significantly higher incidences of infection and anemia were found with TAC/MMF/DAC (p < 0.05 all comparisons). Early steroid withdrawal significantly aided growth at 6 months more so in prepubertal than pubertal children. This was accompanied by significantly better lipid and glucose metabolism profiles without increases in graft rejection or loss.
TWIST trial provides evidence that early steroid withdrawal following abbreviated daclizumab induction and TAC/MMF maintenance immunosuppression improves growth rate in children as early as 6 months after renal transplantation.
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