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Introduction: There is increasing evidence supporting ultrasonography for the determination of optimal chest compression location during cardiac arrest. Radiological studies have demonstrated that in up to 1/3 of patients the aortic root or outflow tract is being compressed during standard CPR. Out-of-hospital-cardiac-arrests (OHCA) could benefit from cardiac localization, undertaken with scaled-down ultrasound equipment by which the largest fluid filled structure in the chest (the heart) is identified to guide optimal compression location. We intend to evaluate 1) where the left ventricle is in supine patients, 2) the accuracy and precision as well as 3) the feasibility and reliability of cardiac localization with a scaled down ultrasound device (bladder scanners). Methods: We are recruiting men and women over the age of 40. The scanning protocol involves using a bladder scanner on a 15-point grid over the subject's left chest and parasternal, midclavicular, and anterior axillary intercostal spaces 3-7. Detected volumes will be recorded, with the presumption that the intercostal space with the largest measured volume is centered over the heart. Echocardiography will then be used to confirm the bladder scanner accuracy and to better describe the patient's internal chest anatomy. Having assessed procedural feasibility on 3 pilot subjects, we are now recruiting 100 participants, with planned interim analysis at 50 participants for sample size reassessment. Maximal volume location frequencies from the echocardiograms will be described and assessed for variation utilizing the goodness-of-fit test. The proportion of agreement across the two modalities regarding the maximal volume location will also be examined. Results: Among the 3 volunteers (pilot study), the scanner identified fluid in 4-8 of 15 intercostal spaces. In each of the three pilot study patients, the maximal volume identified by the bladder scanner was found to be at the parasternal location of the 6th intercostal space. This was also the location of the mid left ventricular diameter on echocardiography. Conclusion: Our literature review and pilot study data support the premise that lay persons and emergency medical personnel may improve compressions (and thus outcomes) during OHCA by using a scaled-down ultrasound to identify the location of optimal compression. We are currently enrolling patients in our study.
Community-acquired pneumonia (CAP) results in substantial numbers of hospitalisations and deaths in older adults. There are known lifestyle and medical risk factors for pneumococcal disease but the magnitude of the additional risk is not well quantified in Australia. We used a large population-based prospective cohort study of older adults in the state of New South Wales (45 and Up Study) linked to cause-specific hospitalisations, disease notifications and death registrations from 2006 to 2015. We estimated the age-specific incidence of CAP hospitalisation (ICD-10 J12-18), invasive pneumococcal disease (IPD) notification and presumptive non-invasive pneumococcal CAP hospitalisation (J13 + J18.1, excluding IPD), comparing those with at least one risk factor to those with no risk factors. The hospitalised case-fatality rate (CFR) included deaths in a 30-day window after hospitalisation. Among 266 951 participants followed for 1 850 000 person-years there were 8747 first hospitalisations for CAP, 157 IPD notifications and 305 non-invasive pneumococcal CAP hospitalisations. In persons 65–84 years, 54.7% had at least one identified risk factor, increasing to 57.0% in those ⩾85 years. The incidence of CAP hospitalisation in those ⩾65 years with at least one risk factor was twofold higher than in those without risk factors, 1091/100 000 (95% confidence interval (CI) 1060–1122) compared with 522/100 000 (95% CI 501–545) and IPD in equivalent groups was almost threefold higher (18.40/100 000 (95% CI 14.61–22.87) vs. 6.82/100 000 (95% CI 4.56–9.79)). The CFR increased with age but there were limited difference by risk status, except in those aged 45 to 64 years. Adults ⩾65 years with at least one risk factor have much higher rates of CAP and IPD suggesting that additional risk factor-based vaccination strategies may be cost-effective.
It has been suggested that cattle have a greater ability to digest fibrous feeds and a lower ability to digest non-fibrous feeds than sheep (Mc Donald et al., 1995). This statement applies mainly to forages and few direct comparisons have been conducted using concentrate ingredients. The digestibility of concentrate ingredients may be influenced by the level of consumption since an increase in intake of a complete diet resulted in a decrease in digestibility (El Khidir and Vestergaard Thomsen, 1983). The aims of this study were (a) to determine the effect of level of consumption by cattle and (b) to examine the effect of animal species (sheep and cattle) on the digestibility of concentrate ingredients.
As a pilot study to investigate whether personalized medicine approaches could have value for the reduction of malaria-related mortality in young children, we evaluated questionnaire and biomarker data collected from the Mother Offspring Malaria Study Project birth cohort (Muheza, Tanzania, 2002–2006) at the time of delivery as potential prognostic markers for pediatric severe malarial anemia. Severe malarial anemia, defined here as a Plasmodium falciparum infection accompanied by hemoglobin levels below 50 g/L, is a key manifestation of life-threatening malaria in high transmission regions. For this study sample, a prediction model incorporating cord blood levels of interleukin-1β provided the strongest discrimination of severe malarial anemia risk with a C-index of 0.77 (95% CI 0.70–0.84), whereas a pragmatic model based on sex, gravidity, transmission season at delivery, and bed net possession yielded a more modest C-index of 0.63 (95% CI 0.54–0.71). Although additional studies, ideally incorporating larger sample sizes and higher event per predictor ratios, are needed to externally validate these prediction models, the findings provide proof of concept that risk score-based screening programs could be developed to avert severe malaria cases in early childhood.
A search has been made for 1612 MHz OH maser emission from OH/IR stars in the Magellanic Clouds. Candidate objects were selected mainly on the basis of their 25μm flux densities and the 25 to 12μm flux ratio as given in the IRAS point source catalog; two known long-period variables and two HII regions (30 Doradus and N159) were also examined. One OH source (IRAS 04553-6825) was detected, this being the first OH/IR star found in the Magellanic Clouds. Upper limits were placed on the flux for 17 other sources. The expansion velocity of the circumstellar material surrounding IRAS 04553-6825, as indicated by the OH peak separation of 11 km s−1, is surprisingly small compared to Galactic sources of similar bolometric and OH luminosity. The OH intensity of IRAS 04553-6825, and the upper flux limits placed on many of the other objects examined, indicate that Magellanic Cloud OH/IR stars do not emit OH as strongly as their Galactic counterparts of similar 25μm/12μm flux ratio. Both the low expansion velocity of IRAS 04553-6825 and the low OH intensity of the Magellanic Cloud infrared sources may be explained by the low metal abundance in the Clouds.
An 8-cm optical telescope is constructed for use at the south pole. It is designed to make photoelectric observations of selected stars continuously through an austral winter. The automated operation is controlled by a computer. The aim is to study the variability of the star γ2 Velorum as well as the condition of the polar sky and the performance of the instrument.
Cannabis use shows a robust dose-dependent relationship with psychosis risk among the general population. Despite this, it has been difficult to link cannabis use with risk for transitioning to a psychotic disorder among individuals at ultra-high risk (UHR) for psychosis. The present study examined UHR transition risk as a function of cannabis use characteristics which vary substantially between individuals including age of first use, cannabis abuse severity and a history of cannabis-induced attenuated psychotic symptoms (APS).
Participants were 190 UHR individuals (76 males) recruited at entry to treatment between 2000 and 2006. They completed a comprehensive baseline assessment including a survey of cannabis use characteristics during the period of heaviest use. Outcome was transition to a psychotic disorder, with mean time to follow-up of 5.0 years (range 2.4–8.7 years).
A history of cannabis abuse was reported in 58% of the sample. Of these, 26% reported a history of cannabis-induced APS. These individuals were 4.90 (95% confidence interval 1.93–12.44) times more likely to transition to a psychotic disorder (p = 0.001). Greater severity of cannabis abuse also predicted transition to psychosis (p = 0.036). However, this effect was mediated by higher abuse severity among individuals with a history of cannabis-induced APS.
Findings suggest that cannabis use poses risk in a subpopulation of UHR individuals who manifest cannabis-induced APS. Whether this reflects underlying genetic vulnerability requires further study. Nevertheless, findings reveal an important early marker of risk with potentially significant prognostic utility for UHR individuals.
In 1985 we began a search for OH/IR objects in the Magellanic Clouds. The first detection was reported by Wood, Bessell & Whiteoak (1986). Subsequent searches have yielded several of these objects and other highly-evolved stars obscured by thick circumstellar shells.
The 1612-MHz OH observations were made using the Parkes 64-m radio telescope. Most of the observations utilized a dual-channel cryogenic receiver providing a system temperature of around 38 K on cold sky. The OH spectra were obtained with the Parkes digital correlator split into 512-channel segments. Bandwidths of 2 MHz provided a resolution of 7.8 kHz (equivalent to 1.5 km s−1 in radial velocity) after Hanning smoothing. The mode of observation has been described by Whiteoak and Gardner (1976). Typically, an integration period of 60 minutes was used; this yielded a detection limit (3a) of around 50 mJy for an OH feature. Detected emission was reobserved with a 1-MHz bandwidth. A search was also made for 1665-MHz OH emission.
While the chief function and methods of operation of the Commission have remained much the same as in the past, there has been a gradual evolution in the nature of the proposals submitted. A greater fraction now come from countries in which the study of astronomy on a professional basis is as yet very recent and more proposals are being received from relatively young astronomers, although admittedly the distinction between a “young” and an “established” astronomer is not always easy to make. The commission may wish to consider whether or not it is advisable to reconsider its guidelines. Grants awarded during the interval 30 November 1981 and 31 January 1985 were the following.
We report the analysis of 154 hours of nearly continuous high-speed photometric data on the pulsating DB white dwarf (DBV) GD 358 obtained during the Whole Earth Telescope (WET) run of May 1990. The Fourier transform (FT) of the light curve is dominated by power in the range from 1200 – 1700μHz with more than 180 significant peaks in the total transform. We also see significant power at the sums and differences of the dominant frequencies, indicating the importance of nonlinear behavior. We can use this data to obtain an accurate total stellar mass, and surface He layer mass. The implied surface He layer mass, if correct, provides a significant and surprising challenge to stellar evolution theory, as well as the theory of chemical mixing.
We present the first results from multi-site observations of the δ Scuti star XX Pyx (CD–24°7599). The observations were carried out as the 17th run of the Delta Scuti Network. We collected 583 hr of B, V time-series photometry, resulting in a detection level (4σ) in the amplitude spectrum of 0.5 mmag. We detect 6 new pulsation frequencies, bringing the total number of frequencies known in this star up 19.
White dwarf stars provide important boundary conditions for the understanding of stellar evolution. An adequate understanding of even these simple stars is impossible without detailed knowledge of their interiors. PG1346+082, an interacting binary white dwarf system, provides a unique opportunity to view the interior of one degenerate as it is brought to light in the accretion disk of the second star as the primary strips material from its less massive companion (see Wood et at. 1987).
PG1346+082 is a photometric variable with a four magnitude variation over a four to five day quasi-period. A fast Fourier transform (FFT) of the light curve shows a complex, time-dependent structure of harmonics. PG1346+082 exhibits flickering – the signature of mass transfer. The optical spectra of the system contain weak emission features during minimum and broad absorption at all other times. This could be attributed to pressure broadening in the atmosphere of a compact object, or to a combination of pressure broadening and doppler broadening in a disk surrounding the compact accretor. No hydrogen lines are observed and the spectra are dominated by neutral helium. The spectra also display variable asymmetric line profiles.
A rationalized lithostratigraphy for the Great Scar Limestone Group of the southeast Askrigg Block is established. The basal Chapel House Limestone Formation, assessed from boreholes, comprises shallow-marine to supratidal carbonates that thin rapidly northwards across the Craven Fault System, onlapping a palaeotopographical high of Lower Palaeozoic strata. The formation is of late Arundian age in the Silverdale Borehole, its northernmost development. The overlying Kilnsey Formation represents a southward-thickening and upward-shoaling carbonate development on a S-facing carbonate ramp. Foraminiferal/algal assemblages suggest a late Holkerian and early Asbian age, respectively, for the uppermost parts of the lower Scaleber Force Limestone and upper Scaleber Quarry Limestone members, significantly younger than previously interpreted. The succeeding Malham Formation comprises the lower Cove Limestone and upper Gordale Limestone members. Foraminiferal/algal assemblages indicate a late Asbian age for the formation, contrasting with the Holkerian age previously attributed to the Cove Limestone. The members reflect a change from a partially shallow-water lagoon (Cove Limestone) to more open-marine shelf (Gordale Limestone), coincident with the onset of marked sea-level fluctuations and formation of palaeokarstic surfaces with palaeosoils in the latter. Facies variations along the southern flank of the Askrigg Block, including an absence of fenestral lime-mudstone in the upper part of the Cove Limestone and presence of dark grey cherty grainstone/packstone in the upper part the Gordale Limestone are related to enhanced subsidence during late Asbian movement on the Craven Fault System. This accounts for the marked thickening of both members towards the Greenhow Inlier.
Several outbreaks of hepatitis A in men who have sex with men (MSM) were reported in the 1980s and 1990s in Australia and other countries. An effective hepatitis A virus (HAV) vaccine has been available in Australia since 1994 and is recommended for high-risk groups including MSM. No outbreaks of hepatitis A in Australian MSM have been reported since 1996. In this study, we aimed to estimate HAV transmissibility in MSM populations in order to inform targets for vaccine coverage in such populations. We used mathematical models of HAV transmission in a MSM population to estimate the basic reproduction number (R0) and the probability of an HAV epidemic occurring as a function of the immune proportion. We estimated a plausible range for R0 of 1·71–3·67 for HAV in MSM and that sustained epidemics cannot occur once the proportion immune to HAV is greater than ~70%. To our knowledge this is the first estimate of R0 and the critical population immunity threshold for HAV transmission in MSM. As HAV is no longer endemic in Australia or in most other developed countries, vaccination is the only means of maintaining population immunity >70%. Our findings provide impetus to promote HAV vaccination in high-risk groups such as MSM.
Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD.
The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them.
PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples.
CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits.
It is yet well understood how mass-loss rates from evolved stars depend on metallicities. With a half of the solar metallicity and the distance of only 50 kpc, the evolved stars of the Large Magellanic Cloud (LMC) are an ideal target for studying mass loss at low metallicity. We have obtained spectra of red-supergiants in the LMC, using the Hershel Space Observatory, detecting CO thermal lines fro J=6–5 up to 15–14 lines. Modelling CO lines with non-LTE Radiative transfer code suggests that CO lines intensities can be well explained with high gas-to-dust ratio, with no obvious reduction in mass-loss rate at the LMC. We conclude that the luminosities of the stars are primary factors on mass-loss rates, rather than the metallicity.
Individuals identified as at ultra-high risk (UHR) for psychosis are at risk of poor functional outcome regardless of development of psychotic disorder. Studies examining longitudinal predictors of poor functioning have tended to be small and report only medium-term follow-up data. We sought to examine clinical predictors of functional outcome in a long-term longitudinal study.
Participants were 268 (152 females, 116 males) individuals identified as UHR 2–14 years previously. A range of clinical and sociodemographic variables were assessed at baseline. Functioning at follow-up was assessed using the Social and Occupational Functioning Assessment Scale (SOFAS).
Baseline negative symptoms, impaired emotional functioning, disorders of thought content, low functioning, past substance use disorder and history of childhood maltreatment predicted poor functioning at follow-up in univariate analyses. Only childhood maltreatment remained significant in the multivariate analysis (p < 0.001). Transition to psychosis was also significantly associated with poor functioning at long-term follow-up [mean SOFAS score 59.12 (s.d. = 18.54) in the transitioned group compared to 70.89 (s.d. = 14.00) in the non-transitioned group, p < 0.001]. Childhood maltreatment was a significant predictor of poor functioning in both the transitioned and non-transitioned groups.
Childhood maltreatment and transition to psychotic disorder independently predicted poor long-term functioning. This suggests that it is important to assess history of childhood maltreatment in clinical management of UHR individuals. The finding that transition to psychosis predicts poor long-term functioning strengthens the evidence that the UHR criteria detect a subgroup at risk for schizophrenia.