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This study proposed the application of a novel immersed boundary method (IBM) for the treatment of irregular geometries using Cartesian computational grids for high speed compressible gas flows modelled using the unsteady Euler equations. Furthermore, the method is accelerated through the use of multiple Graphics Processing Units – specifically using Nvidia’s CUDA together with MPI - due to the computationally intensive nature associated with the numerical solution to multi-dimensional continuity equations. Due to the high degree of locality required for efficient multiple GPU computation, the Split Harten-Lax-van-Leer (SHLL) scheme is employed for vector splitting of fluxes across cell interfaces. NVIDIA visual profiler shows that our proposed method having a computational speed of 98.6 GFLOPS and 61% efficiency based on the Roofline analysis that provides the theoretical computing speed of reaching 160 GLOPS with an average 2.225 operations/byte. To demonstrate the validity of the method, results from several benchmark problems covering both subsonic and supersonic flow regimes are presented. Performance testing using 96 GPU devices demonstrates a speed up of 89 times that of a single GPU (i.e. 92% efficiency) for a benchmark problem employing 48 million cells. Discussions regarding communication overhead and parallel efficiency for varying problem sizes are also presented.
Seasonal influenza virus epidemics have a major impact on healthcare systems. Data on population susceptibility to emerging influenza virus strains during the interepidemic period can guide planning for resource allocation of an upcoming influenza season. This study sought to assess the population susceptibility to representative emerging influenza virus strains collected during the interepidemic period. The microneutralisation antibody titers (MN titers) of a human serum panel against representative emerging influenza strains collected during the interepidemic period before the 2018/2019 winter influenza season (H1N1-inter and H3N2-inter) were compared with those against influenza strains representative of previous epidemics (H1N1-pre and H3N2-pre). A multifaceted approach, incorporating both genetic and antigenic data, was used in selecting these representative influenza virus strains for the MN assay. A significantly higher proportion of individuals had a ⩾four-fold reduction in MN titers between H1N1-inter and H1N1-pre than that between H3N2-inter and H3N2-pre (28.5% (127/445) vs. 4.9% (22/445), P < 0.001). The geometric mean titer (GMT) of H1N1-inter was significantly lower than that of H1N1-pre (381 (95% CI 339–428) vs. 713 (95% CI 641–792), P < 0.001), while there was no significant difference in the GMT between H3N2-inter and H3N2-pre. Since A(H1N1) predominated the 2018–2019 winter influenza epidemic, our results corroborated the epidemic subtype.
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.
We identified and characterized a new cosmocercid nematode species, Cosmocercoides wuyiensis n. sp., through microscopic examination and sequencing of the partial small ribosomal RNA gene (18S rDNA), internal transcribed spacer (ITS) and mitochondrial cytochrome c oxidase subunit 1 (COI) genes. The new species was isolated from the intestine of the Asiatic frog Amolops wuyiensis Liu and Hu, 1975 captured from four localities of the Anhui province in south-east China. Among the 25 recorded species of the Cosmocercoides genus, the morphology of C. wuyiensis n. sp. is closest to that of C. kiliwai and C. malayensis, which were isolated from various Mexican frog and Malaysian lizard species, respectively. However, C. wuyiensis n. sp. displayed several distinguishing features, such as small size of the male body, two spicules of unequal lengths in the male, small gubernaculum, pre-, ad- and post-cloacal caudal rosette papillae in the ratio of 18–24:2:6 and simple papillae in the ratio of 14:multiple:4, circle and number of punctation in each rosette at 1:11–16, sharply conical tail-end and the presence of lateral alae and somatic papillae in both sexes. BLAST and the phylogenetic analyses of the 18S rDNA and ITS sequences indicated that C. wuyiensis n. sp. belonged to the genus Cosmocercoides, while that of the COI gene sequence of C. wuyiensis n. sp. showed 16.36% nucleotide divergence with C. pulcher and 47.99% nucleotide divergence with C. qingtianensis. The morphological and molecular characterization of C. wuyiensis n. sp. provides new taxonomic data for this genus.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
Introduction: Emergency Department (ED) visits related to substance use are rapidly increasing. Despite this, few Canadian EDs have immediate access to addiction medicine specialists or on-site addiction medicine clinics. This study characterized substance-related ED presentations to an urban tertiary care ED and assessed need for an on-site rapid-access addiction clinic (RAAC). Methods: This prospective enrollment, retrospective chart review was conducted from June to August 2018. Adult patients presenting to the ED with a known or suspected substance use disorder were enrolled by any member of their ED care team using a 1-page form. Retrospective chart review of the index ED visit was conducted and the Emergency Department Information System was used to extract information related to the visit. A multivariable logistic regression model was fit to examine factors associated with recommendation for referral to a hypothetical on-site RAAC.This prospective enrollment, retrospective chart review was conducted from June to August 2018. Adult patients presenting to the ED with a known or suspected substance use disorder were enrolled by any member of their ED care team using a 1-page form. Retrospective chart review of the index ED visit was conducted and the Emergency Department Information System was used to extract information related to the visit. A multivariable logistic regression model was fit to examine factors associated with recommendation for referral to a hypothetical on-site RAAC. Results: Of the 557 enrolment forms received, 458 were included in the analysis. 64% of included patients were male and 36% were female, with a median age of 35.0 years. Polysubstance use was seen in 23% of patients, and alcohol was the most common substance indicated (60%), followed by stimulants (32%) and opioids (16%). The median ED length of stay for included patients was 483 minutes, compared to 354 minutes for all-comers discharged from the ED during the study period. 28% of patients had a previous ED visit within 7 days of the index visit, and an additional 17% had a visit in the preceding 30 days. The ED care team indicated ‘Yes’ for RAAC referral from the ED for 66% of patients, for a mean of 4.3 patients referred per day during the study period. Multivariable analysis showed that all substances (except cannabis) correlated to a statistically significant increase in likelihood for indicating ‘Yes’ for RAAC referral from the ED (alcohol, stimulants, opioids, polysubstance; p < 0.05). Patients presenting to the ED with a chief complaint related to substance use were also more likely to be referred (p = 0.01). Conclusion: This retrospective chart review characterized substance-related presentations at a Canadian urban tertiary care ED. Approximately four patients per day would have been referred to an on-site RAAC had one been available. The RAAC model has been implemented in other Canadian hospitals, and collaborating with these sites to begin developing this service would be an important next step.
Recent advances in techniques to generate static ultra-high pressure (>100 GPa) in the diamond anvil cell have significantly enhanced our understanding of the properties of solids under these extreme conditions. In order to characterize the structure of solids at these pressures, X-ray diffraction using synchrotron radiation has become an invaluable tool. Since the highest pressures are attained at the expense of sample volume (~ 100 μm3) , it is best to use the intense radiation available from a synchrotron to study the very small samples used in ultra-high pressure studies. Even with the intense x-ray beams currently available, it is still often desirable to focus the x-ray beam to increase the available flux. We have developed a focusing system which uses multilayer coated spherical mirrors. With this system, intense x-ray beams with sizes smaller than 10 μm by 10 μm can be achieved at a synchrotron radiation beamline. Previously, we used the focusing system for x-ray microprobe experiments.
The seasonality of individual influenza subtypes/lineages and the association of influenza epidemics with meteorological factors in the tropics/subtropics have not been well understood. The impact of the 2009 H1N1 pandemic on the prevalence of seasonal influenza virus remains to be explored. Using wavelet analysis, the periodicities of A/H3N2, seasonal A/H1N1, A/H1N1pdm09, Victoria and Yamagata were identified, respectively, in Panzhihua during 2006–2015. As a subtropical city in southwestern China, Panzhihua is the first industrial city in the upper reaches of the Yangtze River. The relationship between influenza epidemics and local climatic variables was examined based on regression models. The temporal distribution of influenza subtypes/lineages during the pre-pandemic (2006–2009), pandemic (2009) and post-pandemic (2010–2015) years was described and compared. A total of 6892 respiratory specimens were collected and 737 influenza viruses were isolated. A/H3N2 showed an annual cycle with a peak in summer–autumn, while A/H1N1pdm09, Victoria and Yamagata exhibited an annual cycle with a peak in winter–spring. Regression analyses demonstrated that relative humidity was positively associated with A/H3N2 activity while negatively associated with Victoria activity. Higher prevalence of A/H1N1pdm09 and Yamagata was driven by lower absolute humidity. The role of weather conditions in regulating influenza epidemics could be complicated since the diverse viral transmission modes and mechanism. Differences in seasonality and different associations with meteorological factors by influenza subtypes/lineages should be considered in epidemiological studies in the tropics/subtropics. The development of subtype- and lineage-specific prevention and control measures is of significant importance.
Heading date (HD) and flowering date (FD) are critical for yield potential and stability, so understanding their genetic foundation is of great significance in wheat breeding. Three related recombinant inbred line populations with a common female parent were developed to identify quantitative trait loci (QTL) for HD and FD in four environments. In total, 25 putative additive QTL and 20 pairwise epistatic effect QTL were detected in four environments. The additive QTL were distributed across 17 wheat chromosomes. Of these, QHd-1A, QHd-1D, QHd-2B, QHd-3B, QHd-4A, QHd-4B and QHd-6D were major and stable QTL for HD. QFd-1A, QFd-2B, QFd-4A and QFd-4B were major and stable QTL for FD. In addition, an epistatic interaction test showed that epistasis played important roles in controlling wheat HD and FD. Genetic relationships between HD/FD and five yield-related traits (YRTs) were characterized and ten QTL clusters (C1–C10) simultaneously controlling YRTs and HD/FD were identified. The present work laid a genetic foundation for improving yield potential in wheat molecular breeding programmes.
We describe the motivation and design details of the ‘Phase II’ upgrade of the Murchison Widefield Array radio telescope. The expansion doubles to 256 the number of antenna tiles deployed in the array. The new antenna tiles enhance the capabilities of the Murchison Widefield Array in several key science areas. Seventy-two of the new tiles are deployed in a regular configuration near the existing array core. These new tiles enhance the surface brightness sensitivity of the array and will improve the ability of the Murchison Widefield Array to estimate the slope of the Epoch of Reionisation power spectrum by a factor of ∼3.5. The remaining 56 tiles are deployed on long baselines, doubling the maximum baseline of the array and improving the array u, v coverage. The improved imaging capabilities will provide an order of magnitude improvement in the noise floor of Murchison Widefield Array continuum images. The upgrade retains all of the features that have underpinned the Murchison Widefield Array’s success (large field of view, snapshot image quality, and pointing agility) and boosts the scientific potential with enhanced imaging capabilities and by enabling new calibration strategies.
Cultivated pastures in southern China are being used to improve forage productivity and animal performance, but studies on grazing behaviour of goats in these cultivated pastures are still rare. In the current study, the grazing behaviour of Yunling black goats under low (5 goats/ha) and high (15 goats/ha) stocking rates (SRs) was evaluated. Data showed that the proportion of time goats spent on activities was: eating (0.59–0.87), ruminating (0.05–0.35), walking (0.03–0.06) and resting (0.01–0.03). Compared with low SR, goats spent more time eating and walking, and less time ruminating and resting under high SR. Goats had similar diet preferences under both SR and preferred to eat grasses (ryegrass and cocksfoot) more than a legume (white clover). The distribution of eating time on each forage species was more uniform under high v. low SR. Bites/step, bite weight and daily intake were greater under low than high SR. Results suggest that the SR affects grazing behaviour of goats on cultivated pasture, and identifying an optimal SR is critical for increasing bite weight and intake.
This study investigates numerically the performance of applying aerospike nozzle in a hydrogen peroxide mono-propellant propulsion system. A set of governing equations, including continuity, momentum, energy and species conservation equations with extended k-ε turbulence equations, are solved using the finite-volume method. The hydrogen peroxide mono-propellant is assumed to be fully decomposed into water vapor and oxygen after flowing through a catalyst bed before entering the nozzle. The aerospike nozzle is expected to have high performance even in deep throttling cases due to its self-compensating characteristics in a wide range of ambient pressure environments. The results show that the thrust coefficient efficiency (Cf,η) of this work exceeds 90% of the theoretical value with a nozzle pressure ratio (PR) in the range of 20 ~ 45. Many complex gas dynamics phenomena in the aerospike nozzle are found and explained in the paper. In addition, performance of the aerospike nozzle is compared with that of the bell-shape nozzle.
Current feeder space recommendations in laying hen welfare guidelines are inconsistent among and within countries. One determining criterion forming the recommendations (e.g. 12.0 cm/hen for the EU guideline) is that all birds can feed simultaneously. However, if there are other resources in the environment, as in enriched colony housing (ECH), it is unknown whether group-housed hens will choose to feed simultaneously. This study assesses the impact of feeder space on feeding behavior of 60 laying hens (W-36) in ECH using a ultra-high frequency radio-frequency identification-based tracking system. The feeder spaces investigated were 12.0, 9.5, 8.5 and 6.5 cm/hen, achieved by blocking portions of the overall feeder access to keep hens at the same stocking density. Each feeder space treatment, randomly assigned over the course of the experiment, lasted for 7 consecutive days. Feeding behaviors were characterized as daily time spent at the feeder (TS, min/hen-day), daily frequency of visits to the feeder (FV, #/hen-day), and maximum or average percentage of hens feeding simultaneously (MPB, APB, %). Group-average daily feed intake (FI, g/hen-day), water use (WU, g/hen-day), and hen-day egg production (HDEP, %) were also measured. The results revealed that at 12.0 cm/hen, where unoccupied feeder space was present, a maximum of 59.0±1.4% (average of 31.7±0.3%) hens fed simultaneously. No significant differences were detected among 12.0, 9.5 and 8.5 cm/hen in TS (293±10, 286±10 and 281±10 min/hen-day) and MPB (59.0±1.4, 57.3±1.4 and 53.3±1.4%) (P>0.05). The outcome of no significant differences also held true between 12.0 and 9.5 cm/hen in APB (31.7±0.3 v. 30.8±0.3%) and between 9.5 and 8.5 cm/hen in all response variables measured (P>0.05). However, there were significant differences in APB between 6.5 cm/hen and all other treatments; in TS and FV between 6.5 and 9.5 cm/hen; and in MPB between 6.5 and 12 cm/hen (P<0.05). Considerable inter-hen variability was observed in TS (CV varying from 28.0% to 32.1%) and FV (CV varying from 26.5% to 27.8%). All the feeder spaces tested showed no significant impact on FI, WU or HDEP (P>0.05). The results revealed that synchronous feeding of hens in the ECH did not increase with increasing feeder space. However, it is worth noting that lower feeder space may lead to aggression or frustration which was not quantified in the current study.
For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between ‘soil health’, ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.
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.
The physical processes driving the chemical evolution of galaxies in the last ~ 11Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of the star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared observatory like SPICA, will be sensitive enough to peer through the dust-obscured regions of galaxies and access the rest-frame mid- to far-infrared range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ~ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed.
To explore the effects of maternal nutrition on offspring muscle characteristics, a total of 56 sows were assigned to one of the four dietary groups during gestation: control (CON), or control diets supplemented with methyl donor (MET), bisphenol A (BPA), and combined BPA and MET (BPA+MET). Compared with CON offspring, MET offspring showed a higher meat redness value, but lower glycogen content in the longissimus thoracis (LT). Moreover, compared with CON offspring, MET offspring showed lower LT glycogen synthase (GS) mRNA levels at birth and the finishing stage, and increased methylation at the GS promoter. Prenatal BPA exposure reduced the pH and redness value of meat, but increased the lightness value, lactate content, glycolytic potential and lactate dehydrogenase (LDH) enzyme activity in the LT muscle. Prenatal BPA exposure increased LDH mRNA levels in the LT muscle at birth and the finishing stage, and reduced methylation at the LDH promoter. Thus, maternal MET affects muscle GS and LDH expression via DNA methylation, thereby resulting in persistent effects on pork quality.