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Influenza and respiratory syncytial virus (RSV) are common causes of respiratory tract infections and place a burden on health services each winter. Systems to describe the timing and intensity of such activity will improve the public health response and deployment of interventions to these pressures. Here we develop early warning and activity intensity thresholds for monitoring influenza and RSV using two novel data sources: general practitioner out-of-hours consultations (GP OOH) and telehealth calls (NHS 111). Moving Epidemic Method (MEM) thresholds were developed for winter 2017–2018. The NHS 111 cold/flu threshold was breached several weeks in advance of other systems. The NHS 111 RSV epidemic threshold was breached in week 41, in advance of RSV laboratory reporting. Combining the use of MEM thresholds with daily monitoring of NHS 111 and GP OOH syndromic surveillance systems provides the potential to alert to threshold breaches in real-time. An advantage of using thresholds across different health systems is the ability to capture a range of healthcare-seeking behaviour, which may reflect differences in disease severity. This study also provides a quantifiable measure of seasonal RSV activity, which contributes to our understanding of RSV activity in advance of the potential introduction of new RSV vaccines.
Nutritional management of pigs to optimise growth demands pig-specific, time-specific and place-specific determination and provision of nutritional requirement. These elements need to be incorporated into response prediction models that operate in a real-time (not retrospective) closed-loop control environment. This implies appropriate means for the on-line measurement of response to change in nutrient provision, and the simultaneous means for manipulation of feeding level and feed quality. The paper describes how response prediction modelling and response measurement may now be achieved. Optimisation may be pursued with mixed objectives, including those of production efficiency and environmental protection.
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 Molonglo Observatory Synthesis Telescope (MOST) is an 18000 m2 radio telescope located 40 km from Canberra, Australia. Its operating band (820–851 MHz) is partly allocated to telecommunications, making radio astronomy challenging. We describe how the deployment of new digital receivers, Field Programmable Gate Array-based filterbanks, and server-class computers equipped with 43 Graphics Processing Units, has transformed the telescope into a versatile new instrument (UTMOST) for studying the radio sky on millisecond timescales. UTMOST has 10 times the bandwidth and double the field of view compared to the MOST, and voltage record and playback capability has facilitated rapid implementaton of many new observing modes, most of which operate commensally. UTMOST can simultaneously excise interference, make maps, coherently dedisperse pulsars, and perform real-time searches of coherent fan-beams for dispersed single pulses. UTMOST operates as a robotic facility, deciding how to efficiently target pulsars and how long to stay on source via real-time pulsar folding, while searching for single pulse events. Regular timing of over 300 pulsars has yielded seven pulsar glitches and three Fast Radio Bursts during commissioning. UTMOST demonstrates that if sufficient signal processing is applied to voltage streams, innovative science remains possible even in hostile radio frequency environments.
The increased use of the MATRICS Consensus Cognitive Battery (MCCB) to investigate cognitive dysfunctions in schizophrenia fostered interest in its sensitivity in the context of family studies. As various measures of the same cognitive domains may have different power to distinguish between unaffected relatives of patients and controls, the relative sensitivity of MCCB tests for relative–control differences has to be established. We compared MCCB scores of 852 outpatients with schizophrenia (SCZ) with those of 342 unaffected relatives (REL) and a normative Italian sample of 774 healthy subjects (HCS). We examined familial aggregation of cognitive impairment by investigating within-family prediction of MCCB scores based on probands’ scores.
Multivariate analysis of variance was used to analyze group differences in adjusted MCCB scores. Weighted least-squares analysis was used to investigate whether probands’ MCCB scores predicted REL neurocognitive performance.
SCZ were significantly impaired on all MCCB domains. REL had intermediate scores between SCZ and HCS, showing a similar pattern of impairment, except for social cognition. Proband's scores significantly predicted REL MCCB scores on all domains except for visual learning.
In a large sample of stable patients with schizophrenia, living in the community, and in their unaffected relatives, MCCB demonstrated sensitivity to cognitive deficits in both groups. Our findings of significant within-family prediction of MCCB scores might reflect disease-related genetic or environmental factors.
In our attempt to investigate the basic active galactic nucleus (AGN) paradigm requiring a centrally located supermassive black hole (SMBH), a close to Keplerian accretion disk and a jet perpendicular to its plane, we have searched for radio continuum in galaxies with H2O megamasers in their disks. We observed 18 such galaxies with the Very Large Baseline Array in C band (5 GHz, ~2 mas resolution) and we detected 5 galaxies at 8 σ or higher levels. For those sources for which the maser data is available, the positions of masers and those of the 5 GHz radio continuum sources coincide within the uncertainties, and the radio continuum is perpendicular to the maser disk’s orientation within the position angle uncertainties.
Since the IAU (maser-)Symposium 287 in Stellenbosch/South Africa (Jan. 2012), great progress has been achieved in studying extragalactic maser sources. Sensitivity has reached a level allowing for dedicated maser surveys of extragalactic objects. These included, during the last years, water vapor (H2O), methanol (CH3OH), and formaldehyde (H2CO), while surveys related to hydroxyl (OH), cyanoacetylene (HC3N) and ammonia (NH3) may soon become (again) relevant. Overall, with the upgraded Very Large Array (VLA), the Atacama Large Millimeter/submillimeter Array (ALMA), FAST (Five hundred meter Aperture Synthesis Telescope) and the low frequency arrays APERTIF (APERture Tile in Focus), ASKAP (Australian Square Kilometer Array Pathfinder) and MeerKAT (Meer Karoo Array Telescope), extragalactic maser studies are expected to flourish during the upcoming years. The following article provides a brief sketch of past achievements, ongoing projects and future perspectives.
We present polarimetric observations of the 4 ground-state transitions of OH, toward a sample of maser-emitting planetary nebulae (PNe) using the Australia Telescope Compact Array. This sample includes confirmed OH-emitting PNe, confirmed and candidate H2O-maser-emitting PNe. Polarimetric observations provide information related to the magnetic field of these sources. Maser-emitting PNe are very young PNe and magnetic fields are a key ingredient in the early evolution and shaping process of PNe. Our preliminary results suggest that magnetic field strengths may change very rapidly in young PNe.
The class of radio transients called Fast Radio Bursts (FRBs) encompasses enigmatic single pulses, each unique in its own way, hindering a consensus for their origin. The key to demystifying FRBs lies in discovering many of them in order to identity commonalities – and in real time, in order to find potential counterparts at other wavelengths. The recently upgraded UTMOST in Australia, is undergoing a backend transformation to rise as a fast transient detection machine. The first interferometric detections of FRBs with UTMOST, place their origin beyond the near-field region of the telescope thus ruling out local sources of interference as a possible origin. We have localised these bursts to much better than the ones discovered at the Parkes radio telescope and have plans to upgrade UTMOST to be capable of much better localisation still.
Six radio telescopes were operated as the first southern hemisphere VLBI array in April and May 1982. Observations were made at 2.3 and 8.4 Ghz. This array produced VLBI images of 28 southern hemisphere radio sources, high accuracy VLBI geodesy between southern hemisphere sites, and subarcsecond radio astrometry of celestial sources south of declination −45 degrees. This paper discusses only the astrophysical aspects of the experiment.
To evaluate the association of airborne colony-forming units (CFU) at incision sites during implantation of prostheses with the incidence of either incisional or prosthesis-related surgical site infections.
Randomized, controlled trial.
Primary, public institution.
Three hundred patients undergoing total hip arthroplasty, instrumented spinal procedures, or vascular bypass graft implantation.
Patients were randomly assigned in a 1:1 ratio to either the intervention group or the control group. A novel device (Air Barrier System), previously shown to reduce airborne CFU at incision sites, was utilized in the intervention group. Procedures assigned to the control group were performed without the device, under routine operating room atmospheric conditions. Patients were followed up for 12 months to determine whether airborne CFU levels at the incision sites predicted the incidence of incisional or prosthesis-related infection.
Data were available for 294 patients, 148 in the intervention group and 146 in the control group. CFU density at the incision site was significantly lower in the intervention group than in the control group (P<.001). The density of airborne CFU at the incision site during the procedures was significantly related to the incidence of implant infection (P=.021). Airborne CFU densities were 4 times greater in procedures with implant infection versus no implant infection. All 4 of the observed prosthesis infections occurred in the control group.
Reduction of airborne CFU specifically at the incision site during operations may be an effective strategy to reduce prosthesis-related infections. Trial Registration: clinicaltrials.gov Identifier: NCT01610271
We summarise the first year of operation of the Medium Deep Survey - a key project of the HST. Two fields in the LMC are discussed and some preliminary scientific results presented. We also comment on image deconvolution for the extragalactic fields observed as part of the Medium Deep Survey.
With HST and WFPC2, galaxies in the Medium Deep Survey can be reliably classified to magnitudes I814 ≲ 22.0 in the F814W band, at a mean redshift . The main result is the relatively high proportion (~40%) of objects which are in some way irregular or anomalous, and which are of relevance in understanding the origin of the familiar excess population of faint galaxies. These diverse objects include compact galaxies, apparently interacting pairs, galaxies with superluminous starforming regions and diffuse low surface brightness galaxies of various forms. The ‘irregulars’ and ‘peculiar’ galaxies contribute most of the excess counts in the I-band at our limiting magnitude, and may explain the ‘faint blue galaxy’ problem.
Post-traumatic stress disorder (PTSD) is associated with elevated risk for metabolic syndrome (MetS). However, the direction of this association is not yet established, as most prior studies employed cross-sectional designs. The primary goal of this study was to evaluate bidirectional associations between PTSD and MetS using a longitudinal design.
A total of 1355 male and female veterans of the conflicts in Iraq and Afghanistan underwent PTSD diagnostic assessments and their biometric profiles pertaining to MetS were extracted from the electronic medical record at two time points (spanning ~2.5 years, n = 971 at time 2).
The prevalence of MetS among veterans with PTSD was just under 40% at both time points and was significantly greater than that for veterans without PTSD; the prevalence of MetS among those with PTSD was also elevated relative to age-matched population estimates. Cross-lagged panel models revealed that PTSD severity predicted subsequent increases in MetS severity (β = 0.08, p = 0.002), after controlling for initial MetS severity, but MetS did not predict later PTSD symptoms. Logistic regression results suggested that for every 10 PTSD symptoms endorsed at time 1, the odds of a subsequent MetS diagnosis increased by 56%.
Results highlight the substantial cardiometabolic concerns of young veterans with PTSD and raise the possibility that PTSD may predispose individuals to accelerated aging, in part, manifested clinically as MetS. This demonstrates the need to identify those with PTSD at greatest risk for MetS and to develop interventions that improve both conditions.
Impairments in key neuropsychological domains (e.g. working memory, attention) and social cognitive deficits have been implicated as intermediate (endo) phenotypes for bipolar disorder (BD), and should therefore be evident in unaffected relatives.
Neurocognitive and social cognitive ability was examined in 99 young people (age range 16–30 years) with a biological parent or sibling diagnosed with the disorder [thus deemed to be at risk (AR) of developing BD], compared with 78 healthy control (HC) subjects, and 52 people with a confirmed diagnosis of BD.
Only verbal intelligence and affective response inhibition were significantly impaired in AR relative to HC participants; the BD participants showed significant deficits in attention tasks compared with HCs. Neither AR nor BD patients showed impairments in general intellectual ability, working memory, visuospatial or language ability, relative to HC participants. Analysis of BD-I and BD-II cases separately revealed deficits in attention and immediate memory in BD-I patients (only), relative to HCs. Only the BD (but not AR) participants showed impaired emotion recognition, relative to HCs.
Selective cognitive deficits in the capacity to inhibit negative affective information, and general verbal ability may be intermediate markers of risk for BD; however, the extent and severity of impairment in this sample was less pronounced than has been reported in previous studies of older family members and BD cases. These findings highlight distinctions in the cognitive profiles of AR and BD participants, and provide limited support for progressive cognitive decline in association with illness development in BD.
The intensity ratios of HCO+/HCN and HNC/HCN (1-0) reveal the relative influence of star formation and active galactic nuclei (AGN) or black holes on the circum-nuclear gas of a galaxy, allowing the identification of X-ray dominated regions (XDRs) and Photon-dominated regions (PDRs). It is not always clear in the literature how this intensity ratio calculation has been, or should be performed. This paper discusses ratio calculation methods for interferometric data.
We examine the roles of actuaries in UK life offices, along with trends, challenges to and opportunities for actuaries. We carry out an analysis of senior roles in life offices, a questionnaire survey and interviews with relevant senior personnel. We find that actuaries occupy many important roles in life offices and are regarded as having good industry knowledge and technical skills, especially in financial modelling. There are fewer executive directors and more non-executive directors of life offices who are actuaries compared with the position in 1990. A higher proportion of reserved roles is outsourced to consultants than was the case in 1990. Only a small number of Actuarial Function Holders are directors. Actuaries are more siloed than was the case in the past, although actuaries are well represented in the finance and risk functions of many offices. Although actuarial work in connection with the preparation for Solvency II will decline, there will be important ongoing requirements for actuaries following Solvency II implementation. We also see opportunities for actuaries in four areas: in risk management, in financial analysis and management based on Solvency II and international financial reporting standards, in connection with “big data”, and in product development and the customer proposition. There are implications for the examination syllabus, continuing professional development and research.
The paper reports on the growth of group III-Sb’s on silicon, substrate preparation, optimization of AlGaSb metamorphic buffer, formation of defects (threading dislocations, microtwins and anti-phase boundaries) and their effect on the surface morphology and electrical properties of these high hole mobility materials for future III-V CMOS technology. Defect density was found to be 2-3x higher than in similar structures grown on GaAs, resulting in 2x higher roughness. Defects also result in background p-type doping well above 1017 cm-3 causing inversion of polarity from n-type to p-type in thin n-type doped GaSb. MOS Capacitors fabricated on these buffers demonstrate similar characteristics to higher quality GaSb-on-GaAs. The highest hole mobility obtained in a strained InGaSb QW MOS channel grown on silicon is ∼630 cm2/V-s which is ∼30% lower than similar channels grown on GaAs substrates.
The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass star-forming clumps. Exploiting the unique broad frequency range and on-the-fly mapping capabilities of the Australia Telescope National Facility Mopra 22 m single-dish telescope1, MALT90 has obtained 3′ × 3′ maps towards ~2 000 dense molecular clumps identified in the ATLASGAL 870 μm Galactic plane survey. The clumps were selected to host the early stages of high-mass star formation and to span the complete range in their evolutionary states (from prestellar, to protostellar, and on to
regions and photodissociation regions). Because MALT90 mapped 16 lines simultaneously with excellent spatial (38 arcsec) and spectral (0.11 km s−1) resolution, the data reveal a wealth of information about the clumps’ morphologies, chemistry, and kinematics. In this paper we outline the survey strategy, observing mode, data reduction procedure, and highlight some early science results. All MALT90 raw and processed data products are available to the community. With its unprecedented large sample of clumps, MALT90 is the largest survey of its type ever conducted and an excellent resource for identifying interesting candidates for high-resolution studies with ALMA.