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The Australian prime lamb industry is seeking to improve lean meat yield (LMY) as a means to increasing efficiency and profitability across the whole value chain. The LMY of prime lambs is affected by genetics and on-farm nutrition from birth to slaughter and is the total muscle weight relative to the total carcass weight. Under the production conditions of south eastern Australia, many ewe flocks experience a moderate reduction in nutrition in mid to late pregnancy due to a decrease in pasture availability and quality. Correcting nutritional deficits throughout gestation requires the feeding of supplements. This enables the pregnant ewe to meet condition score (CS) targets at lambing. However, limited resources on farm often mean it is difficult to effectively manage nutritional supplementation of the pregnant ewe flock. The impact of reduced ewe nutrition in mid to late pregnancy on the body composition of finishing lambs and subsequent carcass composition remains unknown. This study investigated the effect of moderately reducing ewe nutrition in mid to late gestation on the body composition of finishing lambs and carcass composition at slaughter on a commercial scale. Multiple born lambs to CS2.5 target ewes were lighter at birth and weaning, had lower feedlot entry and exit weights with lower pre-slaughter and carcass weights compared with CS3.0 and CS3.5 target ewes. These lambs also had significantly lower eye muscle and fat depth when measured by ultrasound prior to slaughter and carcass subcutaneous fat depth measured 110 mm from the spine along the 12th rib (GR 12th) and at the C-site (C-fat). Although carcasses were ~5% lighter, results showed that male progeny born to ewes with reduced nutrition from day 50 gestation to a target CS2.5 at lambing had a higher percentage of lean tissue mass as measured by dual energy X-ray absorptiometry and a lower percentage of fat during finishing and at slaughter, with the multiple born progeny from CS3.0 and CS3.5 target ewes being similar. These data suggest lambs produced from multiple bearing ewes that have had a moderate reduction in nutrition during pregnancy are less mature. This effect was also independent of lamb finishing system. The 5% reduction in carcass weight observed in this study would have commercially relevant consequences for prime lamb producers, despite a small gain in LMY.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
Patients with chronic obstructive pulmonary disease (COPD) who experience acute exacerbations usually require treatment with oral steroids or antibiotics, depending on the etiology of the exacerbation. Current management is based on clinician's assessment and judgement, which lacks diagnostic accuracy and results in overtreatment. A test to guide these decisions in primary care is in development. We developed an early decision model to evaluate the cost-effectiveness of this treatment stratification test in the primary care setting in the United Kingdom.
A combined decision tree and Markov model was developed of COPD progression and the exacerbation care pathway. Sensitivity analysis was carried out to guide technology development and inform evidence generation requirements.
The base case test strategy cost GBP 423 (USD 542) less and resulted in a health gain of 0.15 quality-adjusted life-years per patient compared with not testing. Testing reduced antibiotic prescriptions by 30 percent, potentially lowering the risk of antimicrobial resistance developing. In sensitivity analysis, the result depended on the clinical effects of treating patients according to the test result, as opposed to treating according to clinical judgement alone, for which there is limited evidence. The results were less sensitive to the accuracy of the test.
Testing may be cost-saving in primary care, but this requires robust evidence on whether test-guided treatment is effective. High quality evidence on the clinical utility of testing is required for early modeling of diagnostic tests generally.
Primary care clinicians have a central role in managing influenza/influenza-like illness (ILI) during influenza pandemics. This study identifies risk factors for influenza-related complications in children presenting with influenza/ILI in primary care. We conducted a cohort study using routinely collected linked data from the Clinical Practice Research Datalink on children aged 17 years and younger who presented with influenza/ILI during the 2009/10 pandemic. We calculated odds ratios (ORs) for potential risk factors in relation to influenza-related complications, complications requiring intervention, pneumonia, all-cause hospitalisation and hospitalisation due to influenza-related complications within 30 days of presentation. Analyses were adjusted for potential confounders including age, vaccination and socio-economic deprivation. Asthma was a risk factor for influenza-related complications (adjusted OR 1.48, 95% confidence interval (CI) 1.21–1.80, P < 0.001), complications requiring intervention (adjusted OR 1.44, 95% CI 1.11–1.88; P = 0.007), pneumonia (adjusted OR 1.64, 95% CI 1.07–2.51, P = 0.024) and hospitalisation due to influenza-related complications (adjusted OR 2.46, 95% CI 1.09–5.56, P = 0.031). Neurological conditions were risk factors for all-cause hospitalisation (adjusted OR 4.25, 95% CI 1.50–12.07, P = 0.007) but not influenza-related complications (adjusted OR 1.46, 95% CI 0.83–2.56, P = 0.189). Community-based early interventions to prevent influenza-related clinical deterioration should therefore be primarily targeted at children with asthma and neurological conditions.
Phased VLA observations of the Galactic center magnetar J1745-2900 over 8-12 GHz reveal rich single pulse behavior. The average profile is comprised of several distinct components and is fairly stable over day timescales and GHz frequencies. The average profile is dominated by the jitter of relatively narrow pulses. The pulses in each of the four profile components are uncorrelated in phase and amplitude, although the occurrence of pulse components 1 and 2 appear to be correlated. Using a collection of the brightest individual pulses, we verify that the index of the dispersion law is consistent with the expected cold plasma value of 2. The scattering time is weakly constrained, but consistent with previous measurements, while the dispersion measure DM = 1763+3−10 pc cm−3 is lower than previous measurements, which could be a result of time variability in the line-of-sight column density or changing pulse profile shape over time or frequency.
Recent 13C solid state nuclear magnetic resonance studies have demonstrated differences in the composition of sporopollenins (the inert biomolecule forming spore and pollen walls) from the major groups of extant plants. This substance is also the main constituent of fossil spore walls.
We have obtained 13C NMR spectra from three species of Carboniferous lycopod megaspores, and in one case, the associated microspores. Additionally, spores from the Devonian plant Parka decipiens Fleming have been analyzed. The spectra obtained are relatively similar although at present it is unclear how much of this similarity results from diagenesis.
The spectra of the fossil spores have been compared to those obtained from extant lycopods and from other plant groups. The fossil lycopod spores share some of the distinctive features of modern lycopod sporopollenin but are, none the less, very different. The spectra of the fossil species also demonstrate the loss of constituents known to form a significant part of the sporopollenin in extant species. Our studies show that some of the chemical characteristics of sporopollenins are retained in fossil spores, allowing the investigation of evolutionary changes of sporopollenin within a group and facilitating the assignment of taxonomically enigmatic fossil species. Further investigation of a range of fossil material, combined with data obtained from pyrolysis, should provide further information on the composition of sporopollenin from different plant groups and on its diagenesis.
The collective response of electrons in an ultrathin foil target irradiated by an ultraintense (
) laser pulse is investigated experimentally and via 3D particle-in-cell simulations. It is shown that if the target is sufficiently thin that the laser induces significant radiation pressure, but not thin enough to become relativistically transparent to the laser light, the resulting relativistic electron beam is elliptical, with the major axis of the ellipse directed along the laser polarization axis. When the target thickness is decreased such that it becomes relativistically transparent early in the interaction with the laser pulse, diffraction of the transmitted laser light occurs through a so called ‘relativistic plasma aperture’, inducing structure in the spatial-intensity profile of the beam of energetic electrons. It is shown that the electron beam profile can be modified by variation of the target thickness and degree of ellipticity in the laser polarization.
We examine the response of the quiescent chromosphere to the large (E)UV and optical continuum and spectral line radiation field arising from a flare. We show that during a UV Ceti type flare, which displays a large U-band enhancement, a major part of the Balmer line flux may arise from the “quiescent chromosphere”, rather than the heated flare plasma itself. This leads us to distinguish two main phases in the Balmer lines, as first proposed by Houdebine et al. (1989): an early, mainly impulsive, phase, driven by radiative pumping of the quiescent chromosphere, which is mainly correlated with continuum variations, and a later one, related to the thermal flare phase, which arises from the cooling of the flare plasma itself. The effect of the radiative pumping is much larger for stellar (dMe) than for solar flares, due to substantial differences in the flare, relative to the quiescent, level and the quiescent chromospheric density and temperature.
Integrated soft X-ray (8-12A) fluxes for solar flares have been scaled to the equivalent EXOSAT fluxes using spectra obtained from a variety of rocket-based experiments. The data show good agreement with the soft X-ray - Hγ correlation established by Butler et al. (1988) for stellar flares and confirm the basic similarity, in this respect, of flares on the Sun to those on dMe stars.
Four flares were observed on the late-type binary YY Gem in March 1988 during a total monitoring time of 408 min. The flares were unusual in that there is a periodicity in their occurrence, being separated by 48 ± 3 min. Considering the flares to be formed as a stochastic process, we find that the probability of these events occurring by chance is 0.5%. Modelling indicates that for quite reasonable input parameters (e.g. a spot field strength of 1000 G and a filament with mass per unit length of 106g cm-1), the flare periodicity can be explained in terms of filament oscillations. The only requirement is that there should be a filament at these heights where the magnetic field drops inversely proportional to the height.
The emerging statistical properties from the first 50 extrasolar planets are startlingly different from the picture that was imagined prior to 1995. About 0.75% of nearby solar type stars harbor jovian planets in 3 to 5 day circular orbits. Another ∽7% of stars have jupiter–mass companions orbiting in eccentric orbits within 3.5 AU. The mass distribution of substellar companions rises abruptly near 5 MJup and continues increasing down to the detection limit near 1 MJup-Orbital eccentricities correlate positively with semimajor axes, even for planets beyond the tidal circularization zone within 0.1 AU, distinguishing planets from binary stars. The planet bearing stars are metal–rich relative to both nearby stars and to the Sun. Analogs of Solar System planets have not been detected to date as they require precision of 3 m s−1 maintained for more than a decade.
We review the evidence, from rotational modulation, for association of plages and spots on active binaries. We find reasonably convincing support for such an association from IUE SWP observations of RS CVn stars, but little or no evidence from MgII line fluxes. There is a similar lack of evidence for BY Dra systems. The results can be interpreted as evidence for: (a) the presence of active longitudes which persist on some RS CVn stars for several years, (b) high filling factors in MgII emission and (c) lower filling factors, and therefore greater contrast, in SWP emission. There is a suggestion that the association between plages and spots is more clearly seen in longer period RS CVn stars than the very active, short period, systems favoured by IUE observers.
We analyse the new ISCCP (International Satellite Cloud Climatology Project) D2 cloud data to ascertain whether or not a connection between cosmic ray flux and cloud cover exists. Our results indicate that only the low-level cloud follows solar activity over the full period, 1983-1994. Using several proxies for solar activity and the radiative forcing for the ISCCP cloud types, we estimate the possible impact that such a solar-terrestrial connection may have on climate. We conclude that, possibly excluding the most recent decades, much of the warming of the past century can be quantitatively accounted for by the direct and indirect effects of solar activity.
Introduction: Acute upper gastrointestinal (UGI) bleeding is a relatively common emergency resulting in death in 6 to 8% of cases. UGI endoscopy is the intervention of choice which requires procedural sedation and analgesia (PSA). The Halifax Infirmary emergency department (ED) performs 1000 PSAs annually, performed by advanced care paramedics (ACPs). This has been shown safe for other indications for PSA, such as orthopedic procedures. Considering that UGI endoscopy involves upper airway manipulation, and patients are at an increased risk of massive bleeding, this procedure would be expected to be more complex and have an increased risk of adverse events (AEs). This study aims to compare PSA for UGI endoscopy performed by ACPs to that for orthopedic procedures for AEs, airway intervention and medication use. Methods: This study is a retrospective review of an ACP-performed ED PSA quality control database. A dataset was built matching 64 UGI endoscopy PSAs to 192 orthopedic PSAs by propensity scores calculated using age, gender and ASA classification. Outcomes assessed were hypotension (SBP < 100, or 15% decrease from baseline), hypoxia (SaO2 < 90), apnea (> 30sec), vomiting, arrhythmias and death in the ED. The need for airway intervention and medication use was assessed. Results: The UGI endoscopy group was 4.60 times more likely to suffer hypotension than the orthopedic group (OR=4.6, CI:2.2-9.6), and a fifth as likely to require airway repositioning (OR=0.2, CI:0.1-0.5). One endoscopy patient required endotracheal intubation. No patient died in either group. Compared to the orthopedic group, the UGI endoscopy group was one-third as likely to receive fentanyl (OR=0.3, CI:0.2-0.6). When fentanyl was administered, endoscopy patients received an average 26.7 mcg less than orthopedic patients. The endoscopy group was 15.4 times more likely to receive ketamine (OR=15.4, CI:4.7-66.5), and received 34.4 mg less on average. Four endoscopy patients received phenylephrine compared to none in the orthopedic group. There were no other differences. Conclusion: ED PSA for UGI endoscopy appears to differ significantly from that performed for orthopedic procedures. It was associated with more frequent hypotension and increased use of ketamine as a sedative. Patients undergoing UGI endoscopy were less likely to receive fentanyl and require airway repositioning. Only patients in the endoscopy group required intubation or a vasopressor agent.
A photographic survey of variable stars in the Magellanic Clouds is currently in progress at Dunsink Observatory, using photographic material obtained with the ADH telescope. In the course of this investigation a number of Long Period Variables have been measured, most of which lie in the LMC. Several are previously known Harvard Variables (prefixed HV) but some are new discoveries (prefixed DV). The co-ordinates of the new Long Period Variables are listed in Table I.