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We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
Eight ruminally-fistulated wethers were used to examine the temporal effects of afternoon (PM; 1600h) v. morning (AM; 0800 h) allocation of fresh spring herbage from a perennial ryegrass (Lolium perenne L.)-based pasture on fermentation and microbial community dynamics. Herbage chemical composition was minimally affected by time of allocation, but daily mean ammonia concentrations were greater for the PM group. The 24-h pattern of ruminal fermentation (i.e. time of sampling relative to time of allocation), however, varied considerably for all fermentation variables (P⩽0.001). Most notably amongst ruminal fermentation characteristics, ammonia concentrations showed a substantial temporal variation; concentrations of ammonia were 1.7-, 2.0- and 2.2-fold greater in rumens of PM wethers at 4, 6 and 8h after allocation, respectively, compared with AM wethers. The relative abundances of archaeal and ciliate protozoal taxa were similar across allocation groups. In contrast, the relative abundances of members of the rumen bacterial community, like Prevotella 1 (P=0.04), Bacteroidales RF16 group (P=0.005) and Fibrobacter spp. (P=0.008) were greater for the AM group, whereas the relative abundance of Kandleria spp. was greater (P=0.04) for the PM group. Of these taxa, only Prevotella 1 (P=0.04) and Kandleria (P<0.001) showed a significant interaction between time of allocation and time of sampling relative to feed allocation. Relative abundances of Prevotella 1 were greater at 2h (P=0.05), 4h (P=0.003) and 6h (P=0.01) after AM allocation of new herbage, whereas relative abundances of Kandleria were greater at 2h (P=0.003) and 4h (P<0.001) after PM allocation. The early post-allocation rise in ammonia concentrations in PM rumens occurred simultaneously with sharp increases in the relative abundance of Kandleria spp. and with a decline in the relative abundance of Prevotella. All measures of fermentation and most microbial community composition data showed highly dynamic changes in concentrations and genus abundances, respectively, with substantial temporal changes occurring within the first 8h of allocating a new strip of herbage. The dynamic changes in the relative abundances of certain bacterial groups, in synchrony with a substantial diurnal variation in ammonia concentrations, has potential effects on the efficiency by which N is utilised by the grazing ruminant.
Among dinosaurs, megadinosaurs (those over one tonne) have been considered among the best candidates for having had low metabolic rates (LoMRs). Spotila et al (1991) argued that big dinosaurs were gigantotherms that shared thermal characteristics with the large leatherback sea turtle, and Dodson (1991) suggested that giant dinosaurs lived in the slow lane compared to giant mammals. Coulson (1979), Bennett (1991) and Ruben (1991) restored big dinosaurs as “good reptiles” powered by bursts of reptilian hyperanaerobiosis rather than the sustained tachyaerobiosis that powers birds and mammals. Farlow (1990) suggested that large dinosaurs were “damned good reptiles” with fluctuating metabolic rates (MRs), and in 1993 he argued that dinosaurs used a combination of rapid reproduction and intermediate metabolic rates (InMRs) to grow bigger than land mammals. All the above workers, and McNab (1983) and Dunham et al. (1989), have modeled big dinosaurs as LoMR or InMR inertial homeotherms that maintained constant body temperatures on a daily basis.
This study aimed to develop a functional model of subglottic stenosis by inducing direct airway irritation in transplanted mouse laryngotracheal complexes.
Laryngotracheal complexes from C57BL/6 mice were harvested and divided into three groups: uninjured, mechanically injured and chemically injured. Donor laryngotracheal complexes from each group were placed in dorsal subcutaneous pockets of recipient mice. Each week, the transplanted laryngotracheal complexes were harvested, and tissues were fixed, sectioned, and stained with haematoxylin and eosin. Representative slides were reviewed by a blinded pathologist, to determine the formation of granulation tissue, and graded as to the degree of granulation formation.
Direct airway irritation induced granulation tissue formation under the disrupted epithelium of airway mucosa; this was seen as early as two weeks after chemical injury.
Results indicate that granulation tissue formation in a murine model may be an efficient tool for investigating the development and treatment of subglottic stenosis.
Animal slurry is separated in order to avoid excessive nitrogen, phosphorus and potassium (NPK) fertilization of crops in the field. To enhance fertilizer efficiency further, slurry and its separation products may be acidified, for instance in animal houses. The current study quantified the effects of these treatments, both individually and in combination, on fertilizer efficiency, energy production and heavy metal accumulation as a result of manure management. Acidification increased the availability of N to plants in the manure applied, and provided a better match between plant-available NPK in the manure and separation fraction applied to fields and crop need. Total biogas production was not affected by separation, whereas acidification reduced biogas production because the process was inhibited by a low pH and a high sulphur concentration. The amount of copper applied per hectare in the liquid manure to the wheat field was lower than the amount taken up and more zink and copper was applied in the solid fraction to maize field than taken up. The transportation and field application of solids and liquids did not increase management costs when compared to the transportation of slurry alone, but the investment and running costs of separators and manure acidification increased overall management costs.
Vaccination against rumen methanogens offers a practical approach to reduce methane emissions in livestock, particularly ruminants grazing on pasture. Although successful vaccination strategies have been reported for reducing the activity of the rumen-dwelling organism Streptococcus bovis in sheep and S. bovis and Lactobacillus spp. in cattle, earlier approaches using vaccines based on whole methanogen cells to reduce methane production in sheep have produced less promising results. An anti-methanogen vaccine will need to have broad specificity against methanogens commonly found in the rumen and induce antibody in saliva resulting in delivery of sufficiently high levels of antibodies to the rumen to reduce methanogen activity. Our approach has focussed on identifying surface and membrane-associated proteins that are conserved across a range of rumen methanogens. The identification of potential vaccine antigens has been assisted by recent advances in the knowledge of rumen methanogen genomes. Methanogen surface proteins have been shown to be immunogenic in ruminants and vaccination of sheep with these proteins induced specific antibody responses in saliva and rumen contents. Current studies are directed towards identifying key candidate antigens and investigating the level and types of salivary antibodies produced in sheep and cattle vaccinated with methanogen proteins, stability of antibodies in the rumen and their impact on rumen microbial populations. In addition, there is a need to identify adjuvants that stimulate high levels of salivary antibody and are suitable for formulating with protein antigens to produce a low-cost and effective vaccine.
Ruminant-derived methane (CH4), a potent greenhouse gas, is a consequence of microbial fermentation in the digestive tract of livestock. Development of mitigation strategies to reduce CH4 emissions from farmed animals is currently the subject of both scientific and environmental interest. Methanogens are the sole producers of ruminant CH4, and therefore CH4 abatement strategies can either target the methanogens themselves or target the other members of the rumen microbial community that produce substrates necessary for methanogenesis. Understanding the relationship that methanogens have with other rumen microbes is crucial when considering CH4 mitigation strategies for ruminant livestock. Genome sequencing of rumen microbes is an important tool to improve our knowledge of the processes that underpin those relationships. Currently, several rumen bacterial and archaeal genome projects are either complete or underway. Genome sequencing is providing information directly applicable to CH4 mitigation strategies based on vaccine and small molecule inhibitor approaches. In addition, genome sequencing is contributing information relevant to other CH4 mitigation strategies. These include the selection and breeding of low CH4-emitting animals through the interpretation of large-scale DNA and RNA sequencing studies and the modification of other microbial groups within the rumen, thereby changing the dynamics of microbial fermentation.
The Dominion Radio Astrophysical Observatory (DRAO) is carrying out a survey as part of an international collaboration to image the northe, at a common resolution, in emission from all major constituents of the interstellar medium; the neutral atomic gas, the molecular gas, the ionised gas, dust and relativistic plasma. For many of these constituents the angular resolution of the images (1 arcmin) will be more than a factor of 10 better than any previous studies. The aim is to produce a publicly-available database of high resolution, high-dynamic range images of the Galaxy for multi-phase studies of the physical states and processes in the interstellar medium. We will sketch the main scientific motivations as well as describe some preliminary results from the Canadian Galactic Plane Survey/Releve Canadien du Plan Galactique (CGPS/RCPG).
A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (H i) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of H i emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b| < 10°) at all declinations south of δ = +40°, spanning longitudes 167° through 360°to 79° at b = 0°, plus the entire area of the Magellanic Stream and Clouds, a total of 13 020 deg2. The brightness temperature sensitivity will be very good, typically σT≃ 1 K at resolution 30 arcsec and 1 km s−1. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.
The modelling of X-ray pulse profiles from accreting millisecond pulsars is a way to infer masses and radii of neutron stars. We briefly describe how a pulse shape encodes information on the mass and radius, but also depends on other parameters such as hot spot location and observer viewing angle. A numerical model that we have developed is then described. The model includes light bending, time-delay effects, and Doppler effects for photons. The model accounts for oblateness of the neutron star, caused by the rapid rotation, and for scattered light from the surface of the accretion disk. The millisecond pulsar SAX J1808-3658 has multiple observations taken during different outbursts. The observed pulse shapes vary greatly, and it is a challenging test to fit the different observations. Some of the latest results are given.
Fifty-two pediatric oncology patients with central venous catheters (CVCs) who received home care services were studied. Gram-negative organisms were responsible for a greater proportion of CVC-associated bloodstream infections in pediatric oncology patients receiving home care than in hospitalized pediatric oncology patients.
Recent guidelines recommend that where appropriate, procedures for the development of audit in medicine and professions allied to medicine can be replaced by comprehensive multidisciplinary audit of services. The Royal College of Psychiatrists (1990) suggests that clinical audit, involving the work of other staff in the multidisciplinary team, is preferable to purely medical audit. Given the importance of team work in child psychiatry, it seems appropriate to establish a system of audit which enables all disciplines to be involved.
Low fecundity in the laboratory was found in populations of Aedes aegypti (L.) exhibiting Black tergite (Bt), a phenotype characteristic of the feral A. a. formosus (Wlk), whereas high fecundity was found in six domestic populations of A. a. aegyptiin which the phenotype was absent. An investigation of the cause of low oviposition by the feral population indicated that behavioural differences in mating and feeding were not responsible; egg retention was identified as the major factor. Introduction into laboratory procedure of a variable simulating the feral environment, i.e., coconut-shell infusion at the oviposition site, induced a highly significant increase in feral fecundity both through its chemical constituents and visual attraction. Differential response to oviposition site is discussed in relation to the evolution of subspecies of A. aegypti.
Samples of 25 African populations of Aedes aegypti (L.) were examined for variations in scale-colour pattern of palps, halteres, abdominal tergites and metatarsi and in larval body colour. A colour index based on these characters showed domestic populations to be paler than populations found in forests. Classification of phenotypic and genotypic variations in the amount of pale scaling on palps, halteres and, especially, tergites revealed statistically significant differences between some of the populations. Although it was impossible to identify individual mosquitoes, population samples could be identified according to subspecific designations as A. a. formosus (Wlk.) and A. a. aegypti.
1. For 26 weeks, adult male rats were fed on diets containing about 80 % of carbohydrate, given as dextrose, fructose, liquid glucose, or sucrose; their performance was compared with that of rats receiving a standard laboratory cubed diet (41 B) containing 60 % of carbohydrate, mainly as starch. 2. More of diet 41 B was eaten than of any of the diets containing sugars, but only with dextrose was the mean body-weight gain significantly lower than with diet 41 B. 3. No significant differences in body length or girth were produced by the different diets. 4. Compared with those of rats given diet 41B, plasma cholesterol levels were significantly in- creased by fructose and sucrose and to a lesser extent by dextrose, but not by liquid glucose. 5. Compared with those given diet 41 B, the rats given fructose had heavier hearts, kidneys and livers, those given sucrose had heavier hearts and livers, and those given dextrose had heavier hearts. Those given fructose had the heaviest kidneys and livers, and heavier hearts than those given liquid glucose. The organ weights of those given liquid glucose and those given diet 41 B were not significantly different. 6. Compared with the values on diet 41B, carcass and liver fat were both significantly increased by sucrose and fructose but not by dex- trose or liquid glucose. With fructose, liver fat was almost double that with dextrose or liquid glucose. 7. Dry-matter contents of whole carcass and liver followed substantially the same pattern as did the fat contents. 8. Liver protein content was significantly lower on the 80 % carbohydrate diets. The reductions were greatest with fructose and sucrose.
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