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This study identified 26 late invasive primary surgical site infection (IP-SSI) within 4–12 months of transplantation among 2073 SOT recipients at Duke University Hospital over the period 2015–2019. Thoracic organ transplants accounted for 25 late IP-SSI. Surveillance for late IP-SSI should be maintained for at least one year following transplant.
The International VLBI Service for Geodesy and Astrometry (IVS) regularly provides high-quality data to produce Earth Orientation Parameters (EOP), and for the maintenance and realisation of the International Terrestrial and Celestial Reference Frames, ITRF and ICRF. The first iteration of the celestial reference frame (CRF) at radio wavelengths, the ICRF1, was adopted by the International Astronomical Union (IAU) in 1997 to replace the FK5 optical frame. Soon after, the IVS began official operations and in 2009 there was a significant increase in data sufficient to warrant a second iteration of the CRF, ICRF2. The most recent ICRF3, was adopted by the IAU in 2018. However, due to the geographic distribution of observing stations being concentrated in the Northern hemisphere, CRFs are generally weaker in the South due to there being fewer Southern Hemisphere observations. To increase the Southern Hemisphere observations, and the density, precision of the sources, a series of deep South observing sessions was initiated in 1995. This initiative in 2004 became the IVS Celestial Reference Frame Deep South (IVS-CRDS) observing programme. This paper covers the evolution of the CRDS observing programme for the period 1995–2021, details the data products and results, and concludes with a summary of upcoming improvements to this ongoing project.
It is now over thirty years since epidemiological studies revealed a relationship between low birth weight and subsequent risk of developing traditionally adult-onset diseases, such as type 2 diabetes, cardiovascular and renal disease. Initial focus was directed towards the importance of fetal undernutrition. However, it is now recognized that a range of other in utero adverse exposures including chronic fetal hypoxia, maternal over-nutrition and maternal stress can also lead to increased risk of cardio-metabolic and renal diseases in later life. Animal models, including those using non-human primates, sheep and rodents have been critical in demonstrating causality of relationships and helped to define underlying mechanisms, such as epigenetic programming of gene expression and oxidative stress. As the field moves forward in the coming years, these mechanistic studies will help to identify rational intervention strategies to reduce the developmental programming of cardiometabolic and renal dysfunction in suboptimal pregnancy.
Cardiac intensivists frequently assess patient readiness to wean off mechanical ventilation with an extubation readiness trial despite it being no more effective than clinician judgement alone. We evaluated the utility of high-frequency physiologic data and machine learning for improving the prediction of extubation failure in children with cardiovascular disease.
Methods:
This was a retrospective analysis of clinical registry data and streamed physiologic extubation readiness trial data from one paediatric cardiac ICU (12/2016-3/2018). We analysed patients’ final extubation readiness trial. Machine learning methods (classification and regression tree, Boosting, Random Forest) were performed using clinical/demographic data, physiologic data, and both datasets. Extubation failure was defined as reintubation within 48 hrs. Classifier performance was assessed on prediction accuracy and area under the receiver operating characteristic curve.
Results:
Of 178 episodes, 11.2% (N = 20) failed extubation. Using clinical/demographic data, our machine learning methods identified variables such as age, weight, height, and ventilation duration as being important in predicting extubation failure. Best classifier performance with this data was Boosting (prediction accuracy: 0.88; area under the receiver operating characteristic curve: 0.74). Using physiologic data, our machine learning methods found oxygen saturation extremes and descriptors of dynamic compliance, central venous pressure, and heart/respiratory rate to be of importance. The best classifier in this setting was Random Forest (prediction accuracy: 0.89; area under the receiver operating characteristic curve: 0.75). Combining both datasets produced classifiers highlighting the importance of physiologic variables in determining extubation failure, though predictive performance was not improved.
Conclusion:
Physiologic variables not routinely scrutinised during extubation readiness trials were identified as potential extubation failure predictors. Larger analyses are necessary to investigate whether these markers can improve clinical decision-making.
A chloroacetamide herbicide by application timing factorial experiment was conducted in 2017 and 2018 in Mississippi to investigate chloroacetamide use in a dicamba-based Palmer amaranth management program in cotton production. Herbicides used were S-metolachlor or acetochlor, and application timings were preemergence, preemergence followed by (fb) early postemergence, preemergence fb late postemergence, early postemergence alone, late postemergence alone, and early postemergence fb late postemergence. Dicamba was included in all preemergence applications, and dicamba plus glyphosate was included with all postemergence applications. Differences in cotton and weed response due to chloroacetamide type were minimal, and cotton injury at 14 d after late postemergence application was less than 10% for all application timings. Late-season weed control was reduced up to 30% and 53% if chloroacetamide application occurred preemergence or late postemergence only, respectively. Late-season weed densities were minimized if multiple applications were used instead of a single application. Cotton height was reduced by up to 23% if a single application was made late postemergence relative to other application timings. Chloroacetamide application at any timing except preemergence alone minimized late-season weed biomass. Yield was maximized by any treatment involving multiple applications or early postemergence alone, whereas applications preemergence or late postemergence alone resulted in up to 56% and 27% yield losses, respectively. While no yield loss was reported by delaying the first of sequential applications until early postemergence, forgoing a preemergence application is not advisable given the multiple factors that may delay timely postemergence applications such as inclement weather.
Incentivizing the development of interdisciplinary scientific teams to address significant societal challenges usually takes the form of pilot funding. However, while pilot funding is likely necessary, it is not sufficient for successful collaborations. Interdisciplinary collaborations are enhanced when team members acquire competencies that support team success.
Methods:
We evaluated the impact of a multifaceted team development intervention that included an eight-session workshop spanning two half-days. The workshop employed multiple methods for team development, including lectures on empirically supported best practices, skills-based modules, role plays, hands-on planning sessions, and social interaction within and across teams. We evaluated the impact of the intervention by (1) asking participants to assess each of the workshop sessions and (2) by completing a pre/postquestionnaire that included variables such as readiness to collaborate, goal clarity, process clarity, role ambiguity, and behavioral trust.
Results:
The content of the team development intervention was very well received, particularly the workshop session focused on psychological safety. Comparison of survey scores before and after the team development intervention indicated that scores on readiness to collaborate and behavioral trust were significantly higher among participants who attended the workshop. Goal clarity, process clarity, and role ambiguity did not differ among those who attended versus those who did not.
Conclusions:
Multicomponent team development interventions that focus on key competencies required for interdisciplinary teams can support attitudes and cognitions that the literature on the science of team science indicate are predictive of success. We offer recommendations for the design of future interventions.
The Rapid ASKAP Continuum Survey (RACS) is the first large-area survey to be conducted with the full 36-antenna Australian Square Kilometre Array Pathfinder (ASKAP) telescope. RACS will provide a shallow model of the ASKAP sky that will aid the calibration of future deep ASKAP surveys. RACS will cover the whole sky visible from the ASKAP site in Western Australia and will cover the full ASKAP band of 700–1800 MHz. The RACS images are generally deeper than the existing NRAO VLA Sky Survey and Sydney University Molonglo Sky Survey radio surveys and have better spatial resolution. All RACS survey products will be public, including radio images (with
$\sim$
15 arcsec resolution) and catalogues of about three million source components with spectral index and polarisation information. In this paper, we present a description of the RACS survey and the first data release of 903 images covering the sky south of declination
$+41^\circ$
made over a 288-MHz band centred at 887.5 MHz.
Breakthrough Listen is a 10-yr initiative to search for signatures of technologies created by extraterrestrial civilisations at radio and optical wavelengths. Here, we detail the digital data recording system deployed for Breakthrough Listen observations at the 64-m aperture CSIRO Parkes Telescope in New South Wales, Australia. The recording system currently implements two modes: a dual-polarisation, 1.125-GHz bandwidth mode for single-beam observations, and a 26-input, 308-MHz bandwidth mode for the 21-cm multibeam receiver. The system is also designed to support a 3-GHz single-beam mode for the forthcoming Parkes ultra-wideband feed. In this paper, we present details of the system architecture, provide an overview of hardware and software, and present initial performance results.
We have observed the Vela pulsar for 1 year using a Phased Array Feed (PAF) receiver on the 12-m antenna of the Parkes Test-Bed Facility (PTF). These observations have allowed us to investigate the stability of the PAF beam weights over time, to demonstrate that pulsars can be timed over long periods using PAF technology and to detect and study the most recent glitch event that occurred on 12 December 2016. The beam weights are shown to be stable to 1% on time scales on the order of three weeks.
We have observed the Vela pulsar for 1 year using a phased array feed receiver on the 12-m antenna of the Parkes Test-Bed Facility. These observations have allowed us to investigate the stability of the phased array feed beam weights over time, to demonstrate that pulsars can be timed over long periods using phased array feed technology and to detect and study the most recent glitch event that occurred on 2016 December 12. The beam weights are shown to be stable to 1% on time scales on the order of three weeks. We discuss the implications of this for monitoring pulsars using phased array feeds on single dish telescopes.
This study determines the effect of government payments on real agricultural asset values using Bayesian vector autoregression. In developing the empirical model, special attention is focused on the informational content of government payments. The results indicate that government payments to farmers have little effect on real asset values in the long run. In the short run, an increase in government payments to farmers may be associated with decline in asset values.
We present a list of bright (< 17 mag) southern QSOs and bright (< 11 mag) stars that may be suitable for the Hubble Space Telescope link between the Hipparcos astrometric reference frame and the VLBI extragalactic frame. The QSOs have been selected from various lists of radio objects and identifications. The stars have been selected from the Strasbourg (CDS) data base and from the Preliminary Second Cape Photographic Catalogue, and supplemented with stars measured from the SERC IIIa-J Schmidt survey. The list of QSOs and stars have been included in the Hipparcos and HST schedule of observations.
Following the ‘prompt’ radio outburst seen soon after the neutrino emission in SN 1987A (Turtle et al. 1987), we initiated a program to monitor the supernova at the Tidbinbilla Deep Space Communications Complex at 8.4 GHz in a search for radio emission from the expanding remnant. No radio emission has been detected to date (DOY 151, May 30 1988).
In many areas of the country, there is strong competition among agricultural, municipal, industrial and other users of water. Water managers are faced with the problem of allocating available water among alternative uses.
The study [11] upon which this paper is based was a cooperative effort with the Central and Southern Florida Control District which is typical of many water management districts making decisions regarding allocation of a limited amount of water among uses and users. When the District was formed, it was developed with emphasis on facilities to provide relief from flooding. Water management responsibilities such as water supply, recreation and the preservation and enhancement of fish and wildlife have become important to the public and consequently have received recognition by those responsible for managing the water.
The amount of land in urban and other special uses increased more than 50 percent since the 1960s in the South. Rural land converted to urban uses is directly related to increases in population in the South. Urban land-use coefficients were estimated to provide a measure of the amount of land converted to urban uses per person added to the population base. These coefficients indicate that from 1974 to 1987 two-thirds to three fourths of an acre of land was converted to urban uses for each person added to the population base. At this rate, about 12.6 million acres are expected to be converted to urban use in the South during the next two decades.
Conservation efforts use scientific data to provide an adaptive framework wherein habitat and wildlife sustainability can co-exist with human activities. Good science informs decision-makers and facilitates the development of successful conservation approaches. However, conservation concerns for the dugong Dugong dugon in South-east Asia are sufficiently urgent that action must be taken quickly, even though science has not provided complete answers to critical questions. In Johor, Malaysia, aerial surveys were conducted to assess dugong numbers, dugong high-use areas and overlap of dugong sightings with areas of seagrass. Dugong distribution included existing marine parks and locations where known conservation threats exist. We conclude that the Johor islands may represent a significant congregation site for dugongs in Peninsular Malaysia, with as many as 20 dugongs recorded in a single day. The existence of a marine park where the dugong sightings were most prominent is encouraging but only 38% of those sightings fell within the boundaries of the park. Anthropogenic threats need to be assessed and addressed prior to complex development activities such as dredging and coastal reclamation for tourism development in this critical area. We use this case to explore the concept of advancing species conservation through focused research and management, particularly where uncertainties exist because data are scarce.
We report the results of a successful 7-hour 1.4 GHz Very Long Baseline Interferometry (VLBI) experiment using two new stations, ASKAP-29 located in Western Australia and WARK12M located on the North Island of New Zealand. This was the first geodetic VLBI observing session with the participation of these new stations. We have determined the positions of ASKAP-29 and WARK12M. Random errors on position estimates are 150–200 mm for the vertical component and 40–50 mm for the horizontal component. Systematic errors caused by the unmodeled ionosphere path delay may reach 1.3 m for the vertical component.