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We develop rapid chemical vapor sensors and micro gas chromatography (μGC) analyzers based on the optofluidic ring resonator (OFRR). An OFRR is a micro-sized thin-walled glass capillary; the circular cross-section of the capillary acts as an optical ring resonator while the whispering gallery modes or circulating waveguide modes (WGMs) supported by the ring resonator interact with the vapor samples passing through the capillary. The OFRR interior surface is coated with a vapor-sensitive polymer. The analyte and polymer interaction causes the polymer refractive index (RI) and the thickness to change, which is detected as a WGM spectral shift. Owing to the excellent fluidics, the OFRR vapor sensor exhibits sub-second detection and recovery time with a flow rate of 1 mL/min. On-column separation and detection in the OFRR based μGC system is also demonstrated, showing efficient separation of vapor mixtures and presenting highly reproducible retention time for the individual analyte. Compared to the conventional GC system, the OFRR μGC has the advantage of small size, rapid response, and high selectivity over a short length of column.
We describe the design and deployment of GREENBURST, a commensal Fast Radio Burst (FRB) search system at the Green Bank Telescope. GREENBURST uses the dedicated L-band receiver tap to search over the 960–1 920 MHz frequency range for pulses with dispersion measures out to
. Due to its unique design, GREENBURST is capable of conducting searches for FRBs when the L-band receiver is not being used for scheduled observing. This makes it a sensitive single pixel detector capable of reaching deeper in the radio sky. While single pulses from Galactic pulsars and rotating radio transients will be detectable in our observations, and will form part of the database we archive, the primary goal is to detect and study FRBs. Based on recent determinations of the all-sky rate, we predict that the system will detect approximately one FRB for every 2–3 months of continuous operation. The high sensitivity of GREENBURST means that it will also be able to probe the slope of the FRB fluence distribution, which is currently uncertain in this observing band.
The Commensal Real-time Australian Square Kilometre Array Pathfinder Fast Transients survey is the first extensive astronomical survey using phased array feeds. Since January 2017, it has been searching for fast radio bursts in fly’s eye mode. Here, we present a calculation of the sensitivity and total exposure of the survey that detected the first 20 of these bursts, using the pulsars B1641-45 and B0833-45 as calibrators. The beamshape, antenna-dependent system noise, and the effects of radio-frequency interference and fluctuations during commissioning are quantified. Effective survey exposures and sensitivities are calculated as a function of the source counts distribution. Statistical ‘stat’ and systematics ‘sys’ effects are treated separately. The implied fast radio burst rate is significantly lower than the 37 sky−1 day−1 calculated using nominal exposures and sensitivities for this same sample by Shannon et al. (2018). At the Euclidean (best-fit) power-law index of −1.5 (−2.2), the rate is
(sys) ± 3.6 (stat) sky−1 day−1 (
(sys) ± 2.8 (stat) sky−1 day−1) above a threshold of 56.6 ± 6.6(sys) Jy ms (40.4 ± 1.2(sys) Jy ms). This strongly suggests that these calculations be performed for other FRB-hunting experiments, allowing meaningful comparisons to be made between them.
Magnetic field measurements in turbulent plasmas are often difficult to perform. Here we show that for
kG magnetic fields, a time-resolved Faraday rotation measurement can be made at the OMEGA laser facility. This diagnostic has been implemented using the Thomson scattering probe beam and the resultant path-integrated magnetic field has been compared with that of proton radiography. Accurate measurement of magnetic fields is essential for satisfying the scientific goals of many current laser–plasma experiments.
Background: The safety and clinical outcomes of thrombectomy in the 80 years or older age group are not yet clear. Our aim is to provide data from clinical practice to assess the safety and efficacy of endovascular thrombectomy in this age group. Methods: We retrospectively reviewed consecutive patients of age ≥80 referred for thrombectomy procedures at our institutions from 01/01/2015 to 01/09/2015. We collected demographic data, risk factors, clinical and radiological findings, treatment details, clinical and radiological outcomes. Results: Data for 75 patients was included. Baseline clinical characteristics are similar to previous trials. There were MCA occlusions in 49% (37/75) and tandem occlusions in 15% (11/75) patients. 67% (50/75) patients received IVtPA. Good reperfusion (mTICI 2b/3) was achieved in 60% (45/75) patients within 224 minutes. Good clinical outcome (mRS 0-2) at 90 days was achieved in 31% (23/75) patients. Results are similar to HERMES data on patients of age ≥80 and differences will be discussed. Conclusions: Our study adds valuable evidence to the limited data on safety and clinical outcomes in patients 80 years of age and older who undergo thrombectomy. Our findings support the data from clinical trials and confirm that mechanical thrombectomy can be performed safely and in a timely fashion outside of trials with similar results.
Adult schistosomes live in the blood vessels and cannot easily be sampled from humans, so archived miracidia larvae hatched from eggs expelled in feces or urine are commonly used for population genetic studies. Large collections of archived miracidia on FTA cards are now available through the Schistosomiasis Collection at the Natural History Museum (SCAN). Here we describe protocols for whole genome amplification of Schistosoma mansoni and Schistosome haematobium miracidia from these cards, as well as real time PCR quantification of amplified schistosome DNA. We used microgram quantities of DNA obtained for exome capture and sequencing of single miracidia, generating dense polymorphism data across the exome. These methods will facilitate the transition from population genetics, using limited numbers of markers to population genomics using genome-wide marker information, maximising the value of collections such as SCAN.
Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.
To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.
Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.
A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).
The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.
Declaration of interest
Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.
An emerging recombinant norovirus GII.P16/GII.4 Sydney 2012 strain caused a gastroenteritis outbreak amongst attendees at a large health function in regional New South Wales, Australia. This was the third outbreak caused by the recombinant GII.P16/GII.4 Sydney 2012 strain in this region in 2017, which appears to be emerging as a common strain in the Hunter New England region.
Although the pain caused by castration of calves is a significant animal welfare issue for the beef industry, analgesia is not always used for this procedure, largely because of practical limitations associated with injectable forms of pain relief. Novel analgesic formulations have now been developed for livestock to allow topical and buccal administration, offering practical options to improve cattle welfare if shown to be effective. To assess the effects of topical anaesthetic (TA) and buccal meloxicam (BM) on average daily gain (ADG), behaviour and inflammation following surgical castration of beef calves, a total of 50 unweaned bull calves were randomly allocated to: (1) sham castration (SHAM, n=10); (2) surgical castration (C, n=10); (3) surgical castration with pre-operative buccal meloxicam (CBM, n=10); (4) surgical castration with post-operative topical anaesthetic (CTA, n=10); and (5) surgical castration with pre-operative buccal meloxicam and post-operative topical anaesthetic (CBMTA, n=10). Calves were recorded on video for 5 h following treatment and the frequency and duration of specific behaviours displayed by each animal was later observed for 5 min every hour (total of 25 min). Average daily gain was calculated 1, 2 and 6 days following treatment. Scrotal diameter measurements and photographs of wounds were collected from all castrated calves 1, 2 and 6 days following treatment to evaluate inflammation and wound healing. Infrared photographs were used to identify maximum scrotal temperature. Digital photographs were used to visually score wounds on a numerical rating scale of 1 to 5, with signs of inflammation increasing and signs of healing decreasing with progressive scores. Sham castration calves displayed significantly less, and C calves displayed significantly more foot stamps than all other calves (P=0.005). Observations on the duration of time that calves displayed a hypometric ‘stiff gait’ locomotion, indicated that SHAM calves tended to spend no time, C calves tended to spend the greatest time and all other calves tended to spend an intermediate time displaying this behaviour (P=0.06). Maximum scrotal temperatures were lower in CBM and CBMTA calves than C and CTA calves 2 days following treatment (P=0.004). There was no significant effect of treatment on ADG (P=0.7), scrotal diameter (P=0.09) or wound morphology score (P=0.5). These results suggest that TA and BM, alone or in combination, reduced pain and BM reduced inflammation following surgical castration of calves.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
Recent laser-plasma experiments (Fox et al., Phys. Rev. Lett., vol. 111, 2013, 225002; Huntington et al., Nat. Phys., vol. 11(2), 2015, 173–176; Tzeferacos et al., Phys. Plasmas, vol. 24(4), 2017a, 041404; Tzeferacos et al., 2017b, arXiv:1702.03016 [physics.plasm-ph]) report the existence of dynamically significant magnetic fields, whose statistical characterisation is essential for a complete understanding of the physical processes these experiments are attempting to investigate. In this paper, we show how a proton-imaging diagnostic can be used to determine a range of relevant magnetic-field statistics, including the magnetic-energy spectrum. To achieve this goal, we explore the properties of an analytic relation between a stochastic magnetic field and the image-flux distribution created upon imaging that field. This ‘Kugland image-flux relation’ was previously derived (Kugland et al., Rev. Sci. Instrum. vol. 83(10), 2012, 101301) under simplifying assumptions typically valid in actual proton-imaging set-ups. We conclude that, as with regular electromagnetic fields, features of the beam’s final image-flux distribution often display a universal character determined by a single, field-scale dependent parameter – the contrast parameter
– which quantifies the relative size of the correlation length
of the stochastic field, proton displacements
due to magnetic deflections and the image magnification
. For stochastic magnetic fields, we establish the existence of four contrast regimes, under which proton-flux images relate to their parent fields in a qualitatively distinct manner. These are linear, nonlinear injective, caustic and diffusive. The diffusive regime is newly identified and characterised. The nonlinear injective regime is distinguished from the caustic regime in manifesting nonlinear behaviour, but as in the linear regime, the path-integrated magnetic field experienced by the beam can be extracted uniquely. Thus, in the linear and nonlinear injective regimes we show that the magnetic-energy spectrum can be obtained under a further statistical assumption of isotropy. This is not the case in the caustic or diffusive regimes. We discuss complications to the contrast-regime characterisation arising for inhomogeneous, multi-scale stochastic fields, which can encompass many contrast regimes, as well as limitations currently placed by experimental capabilities on one’s ability to extract magnetic-field statistics. The results presented in this paper are of consequence in providing a comprehensive description of proton images of stochastic magnetic fields, with applications for improved analysis of proton-flux images.
Housed pigs are exposed chronically to aerial pollutants, principally dust and ammonia, at concentrations that may affect performance, possibly by raising the incidence and prevalence of multi-factorial respiratory diseases. Tolerable limits for aerial pollutants are unknown. The aim of this experiment was to test the hypothesis that chronic exposure of weaner pigs to controlled concentrations of aerial dust and ammonia lead to slower growth and lower feed intake compared with controls kept in ‘fresh air’.
The purpose of an integrated management system is to optimise both pig performance and environmental protection. A major impediment to this process has been the inability to measure and control the production process in real time, for specific and contemporary pig batches. Optimisation thus requires in-line measurement of pig growth performance, together with the means to change performance with adjustments to feed quantity and quality. This report deals with the use of visual image analysis (VIA) to provide the first of these; measurement of growth. VIA determines, continuously and in-line, the size and shape of the plan view of the pig as it stands at the feeder. Three seminal questions are here addressed. (i) can VIA be used to provide a reliable measure of pig weight, and (ii) how many days are required to elapse before a change in size can be reliably determined and how does the VIA system compare with daily weighing by a conventional weigh-scale, and (iii) can VIA sort pigs according to their shape?
The Hubble Source Catalog (HSC) combines lists of sources detected on images obtained with the WFPC2, ACS and WFC3 instruments aboard the Hubble Space Telescope (HST) and now available in the Hubble Legacy Archive. The catalogue contains time-domain information for about two million of its sources detected using the same instrument and filter on at least five HST visits. The Hubble Catalog of Variables (HCV) aims to identify HSC sources showing significant brightness variations. A magnitude-dependent threshold in the median absolute deviation of photometric measurements (an outlier-resistant measure of light-curve scatter) is adopted as the variability detection statistic. It is supplemented with a cut in χred2 that removes sources with large photometric errors. A pre-processing procedure involving bad image identification, outlier rejection and computation of local magnitude zero-point corrections is applied to the HSC light-curves before computing the variability detection statistics. About 52 000 HSC sources have been identified as candidate variables, among which 7,800 show variability in more than one filter. Visual inspection suggests that ∼70% of the candidates detected in multiple filters are true variables, while the remaining ∼30% are sources with aperture photometry corrupted by blending, imaging artefacts or image processing anomalies. The candidate variables have AB magnitudes in the range 15–27m, with a median of 22m. Among them are the stars in our own and nearby galaxies, and active galactic nuclei.
The Taipan galaxy survey (hereafter simply ‘Taipan’) is a multi-object spectroscopic survey starting in 2017 that will cover 2π steradians over the southern sky (δ ≲ 10°, |b| ≳ 10°), and obtain optical spectra for about two million galaxies out to z < 0.4. Taipan will use the newly refurbished 1.2-m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative ‘Starbugs’ positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6° diameter focal plane, and a purpose-built spectrograph operating in the range from 370 to 870 nm with resolving power R ≳ 2000. The main scientific goals of Taipan are (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H0) to 1% precision, and the growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the total mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of dark matter halo and stellar mass and environment. The final survey, which will be completed within 5 yrs, will consist of a complete magnitude-limited sample (i ⩽ 17) of about 1.2 × 106 galaxies supplemented by an extension to higher redshifts and fainter magnitudes (i ⩽ 18.1) of a luminous red galaxy sample of about 0.8 × 106 galaxies. Observations and data processing will be carried out remotely and in a fully automated way, using a purpose-built automated ‘virtual observer’ software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio; it will become the primary redshift and optical spectroscopic reference catalogue for the local extragalactic Universe in the southern sky for the coming decade.
Shallow ice cores were obtained from widely distributed sites across the West Antarctic ice sheet, as part of the United States portion of the International Trans-Antarctic Scientific Expedition (US ITASE) program. The US ITASE cores have been dated by annual-layer counting, primarily through the identification of summer peaks in non-sea-salt sulfate (nssSO42–) concentration. Absolute dating accuracy of better than 2 years and relative dating accuracy better than 1 year is demonstrated by the identification of multiple volcanic marker horizons in each of the cores, Tambora, Indonesia (1815), being the most prominent. Independent validation is provided by the tracing of isochronal layers from site to site using high-frequency ice-penetrating radar observations, and by the timing of mid-winter warming events in stable-isotope ratios, which demonstrate significantly better than 1 year accuracy in the last 20 years. Dating precision to ±1 month is demonstrated by the occurrence of summer nitrate peaks and stable-isotope ratios in phase with nssSO42–, and winter-time sea-salt peaks out of phase, with phase variation of <1 month. Dating precision and accuracy are uniform with depth, for at least the last 100 years.
A prompt radio burst has been observed from the supernova 1987a in the Large Magellanic Cloud. Observations were made at 0.843, 1.415, 2.29, and 8.41 GHz. At frequencies around 1 GHz, the peak flux density reached about 150 mJy and occurred within four days of the supernova. This event may be a weak precursor to a major radio outburst of the type previously observed in other extragalactic supernovae. Radio monitoring of the supernova is continuing at each of the above frequencies, and coordination is underway of a southern hemisphere VLBI array to map the radio outburst region as it expands. Differential astrometry carried out on prime-focus plates taken with the Anglo-Australian telescope indicates that the component, star 1, of Sanduleak's star SK-69202 is within 0.05 ± 0.13 arcsec of the supernova.
Grassland silage management is generally ad hoc resulting in soil compaction damage. Literature suggests grass yield reductions of 5 to 74% through compaction (UK mean 13%), while a 2015 study, reported here, comparing grass dry matter (DM) yield between controlled traffic farming (CTF) and normal management (N), found a 13.5% (0.80 t ha−1) increase for CTF. Commercially available grass forage equipment with widths of 3 to 12 m set up for CTF reduced trafficked areas from 80%–90% for N to 40%–13%. Economic analysis based on 13% increase in DM for 2 and 3 cut systems, gave an increased grass value between £38 ha−1 and £98 ha−1. CTF for multi-cut grass silage effectively increases yields by reducing compaction and sward damage.
Introduction: Effective trauma resuscitation requires a coordinated team approach, yet there is a significant risk for error. These errors can manifest from sequential system-, team- and knowledge based failures, defined as latent safety threats (LSTs). In situ simulation (ISS), a point-of-care training strategy, provides a novel prospective approach to identify factors that impact patient safety. This study quantified and formulated a hierarchy of LSTs during risk-informed ISS trauma resuscitations. Methods: At a Level 1 trauma centre, we conducted 12 multi-disciplinary, unannounced ISSs to prospectively identify trauma-related LSTs. Four, risk-informed scenarios were developed based on 5 recurring themes found within the trauma program’s morbidity and mortality process. The actual, on-call trauma team participated in the study. Simulations were video recorded with 4 cameras, each positioned at a different angle. Using a framework analysis methodology, human factors experts transcribed and coded the videos. Thematic structure was established deductively based on existing literature and inductively based on observed ISS events. All LSTs were prioritized for future patient safety, systems and ergonomic interventions using the Healthcare Failure Mode and Effect Analysis (HFMEA) matrix. Results: We identified 893 LSTs from 12 simulations. LST analysis resulted in 8 themes subcategorized into 43 codes. Themes were associated with team-, knowledge- or system-related issues. The following themes emerged: situational awareness, provider safety, mental model alignment, team/individual responsibility, team resources, equipment considerations, workplace environment and clinical protocols. The HFMEA hazard scoring process identified 13 high priority codes that required urgent attention and intervention to mitigate negative patient outcomes. Conclusion: A prospective, video-based framework analysis represents a novel and robust approach to LST identification within trauma care. Patterns of LSTs within and between simulations provide a high degree of transparency and traceability for an inter-professional trauma program review. Hazard matrix scoring facilitates the classification and prioritization of human factors interventions intended to improve patient safety.
Chronic fatigue syndrome is likely to be a heterogeneous condition. Previous studies have empirically defined subgroups using combinations of clinical and biological variables. We aimed to explore the heterogeneity of chronic fatigue syndrome.
We used baseline data from the PACE trial, which included 640 participants with chronic fatigue syndrome. Variable reduction, using a combination of clinical knowledge and principal component analyses, produced a final dataset of 26 variables for 541 patients. Latent class analysis was then used to empirically define subgroups.
The most statistically significant and clinically recognizable model comprised five subgroups. The largest, ‘core’ subgroup (33% of participants), had relatively low scores across all domains and good self-efficacy. A further three subgroups were defined by: the presence of mood disorders (21%); the presence of features of other functional somatic syndromes (such as fibromyalgia or irritable bowel syndrome) (21%); or by many symptoms – a group which combined features of both of the above (14%). The smallest ‘avoidant–inactive’ subgroup was characterized by physical inactivity, belief that symptoms were entirely physical in nature, and fear that they indicated harm (11%). Differences in the severity of fatigue and disability provided some discriminative validation of the subgroups.
In addition to providing further evidence for the heterogeneity of chronic fatigue syndrome, the subgroups identified may aid future research into the important aetiological factors of specific subtypes of chronic fatigue syndrome and the development of more personalized treatment approaches.