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Using a commercial X-ray tomography instrument, we have obtained reconstructions of a graded-index optical fiber with voxels of edge length 1.05 µm at 12 tube voltages. The fiber manufacturer created a graded index in the central region by varying the germanium concentration from a peak value in the center of the core to a very small value at the core-cladding boundary. Operating on 12 tube voltages, we show by a singular value decomposition that there are only two singular vectors with significant weight. Physically, this means scans beyond two tube voltages contain largely redundant information. We concentrate on an analysis of the images associated with these two singular vectors. The first singular vector is dominant and images of the coefficients of the first singular vector at each voxel look are similar to any of the single-energy reconstructions. Images of the coefficients of the second singular vector by itself appear to be noise. However, by averaging the reconstructed voxels in each of several narrow bands of radii, we can obtain values of the second singular vector at each radius. In the core region, where we expect the germanium doping to go from a peak value at the fiber center to zero at the core-cladding boundary, we find that a plot of the two coefficients of the singular vectors forms a line in the two-dimensional space consistent with the dopant decreasing linearly with radial distance from the core center. The coating, made of a polymer rather than silica, is not on this line indicating that the two-dimensional results are sensitive not only to the density but also to the elemental composition.
Researchers, including Boyer & Petersen (B&P), commonly use experimental economic studies to draw their conclusions. These studies conventionally strip away context and present participants only with abstract rules. Because context is a strictly necessary component of the decision-making process, it is not clear that inferences about high-level folk psychological concepts (e.g., rationality) can be drawn from decontextualized economic games.
The Taipan galaxy survey (hereafter simply ‘Taipan’) is a multi-object spectroscopic survey starting in 2017 that will cover 2π steradians over the southern sky (δ ≲ 10°, |b| ≳ 10°), and obtain optical spectra for about two million galaxies out to z < 0.4. Taipan will use the newly refurbished 1.2-m UK Schmidt Telescope at Siding Spring Observatory with the new TAIPAN instrument, which includes an innovative ‘Starbugs’ positioning system capable of rapidly and simultaneously deploying up to 150 spectroscopic fibres (and up to 300 with a proposed upgrade) over the 6° diameter focal plane, and a purpose-built spectrograph operating in the range from 370 to 870 nm with resolving power R ≳ 2000. The main scientific goals of Taipan are (i) to measure the distance scale of the Universe (primarily governed by the local expansion rate, H0) to 1% precision, and the growth rate of structure to 5%; (ii) to make the most extensive map yet constructed of the total mass distribution and motions in the local Universe, using peculiar velocities based on improved Fundamental Plane distances, which will enable sensitive tests of gravitational physics; and (iii) to deliver a legacy sample of low-redshift galaxies as a unique laboratory for studying galaxy evolution as a function of dark matter halo and stellar mass and environment. The final survey, which will be completed within 5 yrs, will consist of a complete magnitude-limited sample (i ⩽ 17) of about 1.2 × 106 galaxies supplemented by an extension to higher redshifts and fainter magnitudes (i ⩽ 18.1) of a luminous red galaxy sample of about 0.8 × 106 galaxies. Observations and data processing will be carried out remotely and in a fully automated way, using a purpose-built automated ‘virtual observer’ software and an automated data reduction pipeline. The Taipan survey is deliberately designed to maximise its legacy value by complementing and enhancing current and planned surveys of the southern sky at wavelengths from the optical to the radio; it will become the primary redshift and optical spectroscopic reference catalogue for the local extragalactic Universe in the southern sky for the coming decade.
Appropriate selection of tongue cancer patients considering surgery is critical in ensuring optimal outcomes. The American College of Surgeons' National Surgical Quality Improvement Program (‘ACS-NSQIP’) risk calculator was developed to assess patients' 30-day post-operative risk, providing surgeons with information to guide decision making.
A retrospective review of 30-day actual mortality and morbidity of tongue cancer patients was undertaken to investigate the validity of this tool for South Australian patients treated from 2005 to 2015.
One hundred and twenty patients had undergone glossectomy. Predicted length of stay using the risk calculator was significantly different from actual length of stay. Predicted mortality and other complications were found to be similar to actual outcomes.
The American College of Surgeons' National Surgical Quality Improvement Program risk calculator was found to be effective in predicting post-operative complication rates in South Australian tongue cancer patients. However, significant discrepancies in predicted and actual length of stay may limit its use in this population.
We present results from a multiwavelength study of the blazar PKS 1954–388 at radio, UV, X-ray, and gamma-ray energies. A RadioAstron observation at 1.66 GHz in June 2012 resulted in the detection of interferometric fringes on baselines of 6.2 Earth-diameters. This suggests a source frame brightness temperature of greater than 2 × 1012 K, well in excess of both equipartition and inverse Compton limits and implying the existence of Doppler boosting in the core. An 8.4-GHz TANAMI VLBI image, made less than a month after the RadioAstron observations, is consistent with a previously reported superluminal motion for a jet component. Flux density monitoring with the Australia Telescope Compact Array confirms previous evidence for long-term variability that increases with observing frequency. A search for more rapid variability revealed no evidence for significant day-scale flux density variation. The ATCA light-curve reveals a strong radio flare beginning in late 2013, which peaks higher, and earlier, at higher frequencies. Comparison with the Fermi gamma-ray light-curve indicates this followed ~ 9 months after the start of a prolonged gamma-ray high-state—a radio lag comparable to that seen in other blazars. The multiwavelength data are combined to derive a Spectral Energy Distribution, which is fitted by a one-zone synchrotron-self-Compton (SSC) model with the addition of external Compton (EC) emission.
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.
Our knowledge of the universe comes from recording the photon and particle fluxes incident on the Earth from space. We thus require sensitive measurement across the entire energy spectrum, using large telescopes with efficient instrumentation located on superb sites. Technological advances and engineering constraints are nearing the point where we are recording as many photons arriving at a site as is possible. Major advances in the future will come from improving the quality of the site. The ultimate site is, of course, beyond the Earth’s atmosphere, such as on the Moon, but economic limitations prevent our exploiting this avenue to the degree that the scientific community desires. Here we describe an alternative, which offers many of the advantages of space for a fraction of the cost: the Antarctic Plateau.
EURO-GANEX aims to recycle both major and minor actinides. As the final waste
composition is free from actinides, adapted immobilization matrices should be
developed. Synroc is a potential wasteform that has proven itself to be
efficient in immobilizing high-level wastes (HLW). In this study, a new
composition of Synroc, Synroc-Z, is designed and characterized. The key
modification is in decreasing the amount of zirconolite phase, which is the main
host phase for actinides and increasing the amount of other phases (hollandite
and perovskite). As designed the obtained amount of zirconolite is lower than in
Synroc-C compositions. Synroc-Z samples were synthesized with a waste loading of
20 wt.% at various temperatures and pressures via hot-pressing to determine the
optimum process parameters, which were determined to be 1150-1200°C and
20 MPa, respectively.
Selective area growth of thin films reduces the number of steps in microfabrication processing and enables novel device structures. Here, we report, for the first time, selective area epitaxy of an oxide material on a GaN surface. Chlorination of the GaN surface via wet chemical processing is found effective to disrupt Mg adsorption and selectively prevent molecular beam epitaxy growth of MgO. MgO films grown on neighboring, nonchlorinated surfaces are epitaxial with a (111) MgO||(0001) GaN crystallographic relationship. Better than 3 μm lateral resolution for the selective area growth of MgO on GaN is demonstrated.
Although a few studies consider the sustainability of animal farming systems along the three classical main pillars (economy, environment and society), most studies on pig farming systems address only one of these pillars. The present paper is the introduction to a series of companion papers presenting the results of a study undertaken within the EU-supported project Q-PorkChains, aiming at building a comprehensive tool for the evaluation of pig farming systems, which is robust to accommodate the large variability of systems existing in Europe. The tool is mostly based on questions to farmers and comprises a total of 37 dimensions distributed along eight themes: Animal Welfare, Animal Health, Breeding Programmes, Environmental Sustainability, Meat Safety, Market Conformity, Economy and Working Conditions. The paper describes the procedure that was used for building the tool, using it on 15 contrasted pig farming systems and analysing the results. The evaluated systems are briefly described and a short overview of the dimensions is provided. Detailed descriptions of the theme-wise tools and results, as well as the results of an integrated evaluation, are available in the companion papers.
Low weight at birth has previously been shown to be associated with a number of adult diseases such as type 2 diabetes, cardiovascular disease, high blood pressure, and obesity later in life. Genome-wide association studies (GWAS) have been published for singleton-born individuals, but the role of genetic variation in birth weight (BW) in twins has not yet been fully investigated. A GWAS was performed in 4,593 female study participants with BW data available from the TwinsUK cohort. A genome-wide significant signal was found in chromosome 9, close to the NTRK2 gene (OMIM: 600456). QIMR, an Australian twin cohort (n = 3,003), and UK-based singleton-birth individuals from the Hertfordshire cohort (n = 2,997) were used as replication for the top two single nucleotide polymorphism (SNPs) underpinning this signal, rs12340987 and rs7849941. The top SNP, rs12340987, was found to be in the same direction in the Australian twins and in the singleton-born females (fixed effects meta-analysis beta = -0.13, SE = 0.02, and p = 1.48 × 10−8) but not in the singleton-born males tested. These findings provide an important insight into the genetic component of BW in twins who are normally excluded due to their lower BW when compared with singleton births, as well as the difference in BW between twins. The NTRK2 gene identified in this study has previously been associated with obesity.