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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.
Weed management is a major challenge in organic crop production, and organic farms generally harbor larger weed populations and more diverse communities compared with conventional farms. However, little research has been conducted on the effects of different organic management practices on weed communities and crop yields. In 2014 and 2015, we measured weed community structure and soybean [Glycine max (L.) Merr.] yield in a long-term experiment that compared four organic cropping systems that differed in nutrient inputs, tillage, and weed management intensity: (1) high fertility (HF), (2) low fertility (LF), (3) enhanced weed management (EWM), and (4) reduced tillage (RT). In addition, we created weed-free subplots within each system to assess the impact of weeds on soybean yield. Weed density was greater in the LF and RT systems compared with the EWM system, but weed biomass did not differ among systems. Weed species richness was greater in the RT system compared with the EWM system, and weed community composition differed between RT and other systems. Our results show that differences in weed community structure were primarily related to differences in tillage intensity, rather than nutrient inputs. Soybean yield was lower in the EWM system compared with the HF and RT systems. When averaged across all four cropping systems and both years, soybean yield in weed-free subplots was 10% greater than soybean yield in the ambient weed subplots that received standard management practices for the systems in which they were located. Although weed competition limited soybean yield across all systems, the EWM system, which had the lowest weed density, also had the lowest soybean yield. Future research should aim to overcome such trade-offs between weed control and yield potential, while conserving weed species richness and the ecosystem services associated with increased weed diversity.
My first day as a temporary employee at the actuarial consulting firm Harold, Adams, McNutt & Joy, LLP, was in many respects just another day at the office, another day of precarious work in a gig economy. My workstation was familiar, though not my own: it featured a slightly outdated personal computer, a laser printer, a telephone, a lamp, and various supplies all hemmed in by grey cubicle walls, pinned with a few personal photographs and work-related charts (fig. 1). I followed instructions left by the desk's usual inhabitant, sticky notes pasted to my computer monitor directing me to open folders on the computer, listen to audio recordings, and monitor my phone. A woman's voice played from computer speakers or the phone receiver, she identified herself as Sarah Jane Tully and trained me to fill out the actuarial tables that would consume my workday. Emails arrived from coworkers, letting me know when clients had died and which tables needed updating. Entering their data into spreadsheets, I watched their mortality become obscured by the computational logic of insurers. I filled downtime between tasks by poking around Sarah Jane's computer. I hoped (mischievously) to find evidence of corporate malfeasance, but only uncovered her vacation plans; I empathized with the modesty of her middle-class beach fantasies. Occasionally the printer sprang to life, delivering love notes meant for someone else, full of lustful details. These I perused bemusedly. When I updated actuarial charts, the printer would provide brief biographies: names, images, and narratives of those who had passed on a single sheet of paper. These absorbed me totally. I read them closely and internalized the details of the images, before the digital bleating of a new email in my inbox would break the reverie and return me to the day's work.
This was my experience of the play Temping in its initial run at Dixon Place in New York City in August 2014. Directed by Michael Rau, written by Michael Yates Crowley, and designed by Asa Wember, Temping is a production of Wolf 359, a self-described “Narrative Technology Company” that has been staging original works authored and often performed by Crowley in the United States and Europe since 2007.
Urinary tract infections (UTIs) are common among college-aged women and often recur. Some antibiotics recommended to treat UTIs trigger dysbiosis of intestinal and vaginal microbiomes – where uropathogens originate, though few studies have investigated associations between these therapies with recurrent infections. We retrospectively analysed the electronic medical records of 6651 college-aged women diagnosed with a UTI at a US university student health centre between 2006 and 2014. Women were followed for 6 months for incidence of a recurrent infection. In a secondary analysis, associations in women whose experienced UTI recurrence within 2 weeks were also considered for potential infection relapse. Logistic regression was used to assess associations between infection recurrence or relapse and antibiotics prescribed, in addition to baseline patient characteristics including age, race/ethnicity, region of origin, year of encounter, presence of symptomology, pyelonephritis, vaginal coinfection and birth control consultation. There were 1051 instances of infection recurrence among the 6620 patients, indicating a prevalence of 16%. In the analysis of patient characteristics, Asian women were statistically more likely to experience infection recurrence whereas African American were less likely. No significant associations were identified between the antibiotic administered at the initial infection and the risk of infection recurrence after multivariable adjustment. Treatment with trimethoprim-sulphamethoxazole and being born outside of the USA were significantly associated with increased odds of infection relapse in the multivariate analysis. The results of the analyses suggest that treatment with trimethoprim-sulphamethoxazole may lead to an increased risk of UTI relapse, warranting further study.
The overall objective of a series of experiments to investigate ‘metabolic stress’ was to examine the relationships between ‘metabolic load’, disease and other parameters associated with the welfare of the dairy cow. In the main, these used several well controlled herd based studies complimented with more basic and strategic investigations. In this paper we compare and contrast practical aspects of health and welfare in two high genetic merit herds managed at the extremes of inputs and outputs for dairy farming in south-west Scotland. The hypothesis was that high output herds would have more health and welfare problems than low input herds. Two herds (70 Holstein-Friesian cows each) at SAC Acrehead Dumfries of a similar genetic background (overall in the top 5% of UK cows by PIN and ITEM), were housed in identical buildings and tended by the same herdsman. Both herds had autumn- and spring-calving cattle. The ‘low input’ herd (LI) was given a minimum of concentrate (approx. 0.5 t per cow per year) and milked twice a day and had a restricted quota of 385 000 l. The ‘high output’ herd (HO) was managed for high yields (unrestricted quota) and was given concentrates (2 t per cow per year) and forage ad libitum and milked three times daily. In 1995-96 the sole source of winter forage was grass/clover silage (LI) or grass silage (HO) but in 1996-1998 ensiled cereal and fodder beet were included in both diets. ‘Metabolic load’ could only be inferred from overall inputs, milk outputs, weight loss, body condition score and behaviour. There were significant differences in 305-day lactation yields between herds, and season of calving especially in 1995-96 (LI autumn; 5952 l at 30 g/kg protein (P); LI spring; 5741 l, 32.5 g/kg P; HO autumn; 9541 l at 32.8 g/kg P; HO spring; 8402 l, 32.6 g/kg P). LI weight and body condition-score losses were greatest in this year and behavioural studies showed substantial differences in feeding time (HO < LI, P < 0.05) and total lying time (LI < HO; P < 0.05). However these differences were much less marked in subsequent years. There was a significant difference in the prevalence and incidence of clinical lameness between herds (HO > LI; P < 0.05) and season (autumn > spring P < 0.05) but not for mastitis or metabolic disease. An in-depth study of subclinical claw horn lesion development in first calving heifers showed significant differences between herds in 1996-97 (LI > HO, P < 0.05) but none in 1995-96. There was a significant difference for season in both years (autumn > spring, P < 0.05). Analysis of blood biochemistry parameters of samples taken at approximately 1 month after calving showed some significant differences between LI and HO generally indicating a greater ‘metabolic load’ for LI. Although the full effects of ‘metabolic load’ on immune function and reproduction are dealt with elsewhere our preliminary data showed no significant differences between herds for the former but some significant differences for the latter, in particular there were differences in aspects of the progesterone profiles between herds and more importantly between seasons. However these latter differences were not clearly reflected in conception rates. It was concluded that the hypothesis was not fully sustained and that both systems had pitfalls in terms of welfare. The three major areas causing difficulties for both systems were the need first to ensure adequate intake of forage; secondly to limit the environmental challenge to the feet and udder and finally to marry these systems to the factors limiting reproduction, primarily calving season and ability of reproduction management.
Previous studies have demonstrated that including fish oil (FO) in the diet of beef cattle resulted in increased long chain C20n -3 PUFA (20:5n -3 and 22:6n -3) in muscle resulting in a lower n -6:n -3 ratio (Scollan et al., 2001). However, it may result in negative effects on colour shelf life and organoleptic properties (Vatansever et al., 2000). Fish oil is also a good inhibitor of biohydrogenation in the rumen, resulting in increased production of 18:1trans (TVA), the precursor for conjugated linoleic acid (CLA cis -9, trans -11) in muscle. This study investigated the effects of incremental levels of fish oil in the diet on the fatty acid composition of the m. longissimus dorsi and meat quality.
We have previously demonstrated that feeding red clover relative to grass silage results in meat characterised by higher levels of polyunsaturated fatty acids (PUFA) but reduced shelf life which was associated with lower levels of vitamin E in the muscle (Scollan et al., 2006). Colour shelf life could be ameliorated by feeding additional vitamin E (Scollan et al., 2006). Feeding red clover silage followed by finishing off pasture may help alleviate the problem of colour shelf life while maintaining the benefit of the legume in delivering higher PUFA into meat. Hence this study examined feeding red clover compared with grass silage during the winter, following by a summer finishing period at grass, on fatty acid composition, vitamin E content of meat, colour shelf life and sensory attributes of beef.
In studies of extragalactic radio sources with multiple compact components the determination of which components, if any, are stationary and which moving is of importance. In order to learn about the radio properties of the individual components it is also relevant to be able to register maps made at several wavelengths. Both tasks are usually not possible with VLBI because of the irrecoverable corruption of the fringe phase introduced by the propagation medium and the instrumentation. However, when two or more compact radio sources are separated by only a small angle from each other difference techniques can be used to help tackle both questions.
As a continuation of our earlier work (Gottesman and Hunter, 1982), we have reobserved the HI emission from the galaxy NGC 3992. We have combined all the data and produced new maps, at a significantly improved signal-to-noise ratio, of the gas density and velocity distribution with resolutions of ~ 22″ and 25 km s−1. The resultant, angle averaged, HI rotational velocity is shown in Figure 1 for the symmetric and nearly circular flows for r ≤ 3.35′ from the center (r ≤ 14.0 kpc, assuming de Vaucouleurs' (1979) distance of 14.2 mpc for NGC 3992). Shown, also, in Figure 1 is a fit to the observations provided by a Toomre disk of index n = o. No attempt was made to fit the observational data within 1′, in view of the low signal to noise.
We report observations of the atomic hydrogen properties of the barred spiral galaxies NGC 3992 and NGC 4731. These systems were observed in 1980 and 1981 with the VLA telescope of the National Radio Astronomy Observatory. In Table 1 we list the systemic parameters of interest.
The equilibration time
in response to a change in flux from
after an injection period
applied to either a low-Reynolds-number gravity current or one propagating through a porous medium, in both axisymmetric and one-dimensional geometries, is shown to be of the form
, independent of all the remaining physical parameters. Numerical solutions are used to investigate
for each of these situations and compare very well with experimental results in the case of an axisymmetric current propagating over a rigid horizontal boundary. Analysis of the relaxation towards self-similarity provides an illuminating connection between the excess (deficit) volume from early times and an asymptotically equivalent shift in time origin, and hence a good quantitative estimate of
. The case
of equilibration after ceasing injection at time
is a singular limit. Extensions to high-Reynolds-number currents and to the case of a constant-volume release followed by constant-flux injection are discussed briefly.
There is a genetic contribution to the risk of suicide, but sparse prior research on the genetics of suicidal ideation.
Active and passive suicidal ideation were assessed in a Sri Lankan population-based twin registry (n = 3906 twins) and a matched non-twin sample (n = 2016). Logistic regression models were used to examine associations with socio-demographic factors, environmental exposures and psychiatric symptoms. The heritability of suicidal ideation was assessed using structural equation modelling.
The lifetime prevalence of any suicidal ideation was 13.0% (11.7–14.3%) for men; 21.8% (20.3–23.2%) for women, with no significant difference between twins and non-twins. Factors that predicted suicidal ideation included female gender, termination of marital relationship, low education level, urban residence, losing a parent whilst young, low standard of living and stressful life events in the preceding 12 months. Suicidal ideation was strongly associated with depression, but also with abnormal fatigue and alcohol and tobacco use. The best fitting structural equation model indicated a substantial contribution from genetic factors (57%; CI 47–66) and from non-shared environmental factors (43%; CI 34–53) in both men and women. In women this genetic component was largely mediated through depression, but in men there was a significant heritable component to suicidal ideation that was independent of depression.
These are the first results to show a genetic contribution to suicidal ideation that is independent of depression outside of a high-income country. These phenomena may be generalizable, because previous research highlights similarities between the aetiology of mental disorders in Sri Lanka and higher-income countries.
Introduction: Trauma teams have been shown to improve outcomes in severely injured patients. The criteria used to mobilize trauma teams is highly variable and debated. This study was undertaken to define the triage accuracy at our level 1 trauma centre and identify the criteria predictive of appropriate activations. Methods: A 3-month prospective observational study was performed and all patients presenting to the ER who received a trauma flag were identified. Patient demographics, vital signs, trauma team activation and criteria for activation were documented. Trauma activations were deemed appropriate if the patient met any of the following; airway intervention, needle/tube thoracostomy, resuscitative thoracotomy, ED blood product transfusion, invasive hemodynamic monitoring, central line insertion, emergent OR (<8 hours), admission to ICU, and death within 72 hours. Over and undertriage rates were calculated and a multivariate logistic regression was performed to identify activation criteria predictive of appropraite activations. The activation criteria were then modified and the prospective study was repeated to assess the impact on triage accuracy. Results: Between September to December 2015, 188 patients received a trauma flag. 137 patients met the activation criteria, however only 78 received a trauma team activation. 57% of patients who had TTA met the definition of appropriate activation, while 45% who met criteria for activation met the definition of appropriate. The rates of under and overtriage were 30.4% and 30.3%, respectively. Logistic regression revealed the following criteria to be predictive of appropriate activation; hypotension (OR 10.2 95% CI 2.3,45.5), arrival by HEMS (OR 3.2, 95% CI 1.4,7.6), pedestrian struck (OR 3.5, 95% CI 1.4,8.5) and fall (OR 5.1, 95% CI 1.7, 15.1). Tachycardia (OR 1.1, 95% 0.3,4.6) and high energy MVC (OR 1.4, 95% CI 0.7,3.1) were not found to be predictive. The post-modification study occured between September to December 2016. Data analysis to assess the impact of criteria alteration are currently underway and will be presented at CAEP 2017. Conclusion: Triage accuracy for the mobilization of a multi-disciplinary trauma team is important, both to ensure optimal patient care as well as to reduce unnecessary resource strain. Our previous criteria lead to high rates of undertriage and subsequent modifications have been made. The impact of these changes will be ascertained and presented at CAEP 2017.
Obsessive–compulsive disorder (OCD) has been linked to functional abnormalities in fronto-striatal networks as well as impairments in decision making and learning. Little is known about the neurocognitive mechanisms causing these decision-making and learning deficits in OCD, and how they relate to dysfunction in fronto-striatal networks.
We investigated neural mechanisms of decision making in OCD patients, including early and late onset of disorder, in terms of reward prediction errors (RPEs) using functional magnetic resonance imaging. RPEs index a mismatch between expected and received outcomes, encoded by the dopaminergic system, and are known to drive learning and decision making in humans and animals. We used reinforcement learning models and RPE signals to infer the learning mechanisms and to compare behavioural parameters and neural RPE responses of the OCD patients with those of healthy matched controls.
Patients with OCD showed significantly increased RPE responses in the anterior cingulate cortex (ACC) and the putamen compared with controls. OCD patients also had a significantly lower perseveration parameter than controls.
Enhanced RPE signals in the ACC and putamen extend previous findings of fronto-striatal deficits in OCD. These abnormally strong RPEs suggest a hyper-responsive learning network in patients with OCD, which might explain their indecisiveness and intolerance of uncertainty.
We prove that, for Poisson transmission and recovery processes, the classic susceptible→infected→recovered (SIR) epidemic model of Kermack and McKendrick provides, for any given time t>0, a strict lower bound on the expected number of susceptibles and a strict upper bound on the expected number of recoveries in the general stochastic SIR epidemic. The proof is based on the recent message passing representation of SIR epidemics applied to a complete graph.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
The evolution of a tandem accelerator 14C dating system at Chalk River is recounted. Background problems and sources of instability are discussed and solutions are described. Details of sample chemistry and source preparation are presented.
The Chalk River Tandem Accelerator Mass Spectrometry System has reached a state of reliable measurement of 14C using 2 to 5mg elemental carbon prepared by Mg reduction of CO2. For two comparisons of a near-modern unknown with the NBS oxalic acid standard we obtain a total error of ∼±4.5%, consisting of a random system error of about ±3.5% combined with the statistical counting error. Measurements have been made on 70 samples in 30 days of running time during the past year. Samples included deep rock carbonates, cosmogenic 14C in meteorites, charcoal from earthquake fault zones, collagen of bone artifacts and fossil beetle-fragments.