Vertices of Lie Modules

Let Lie(n) be the Lie module of the symmetric group S_n over a field F of characteristic p>0, that is, Lie(n) is the left ideal of FS_n generated by the Dynkin-Specht-Wever element. We study the problem of parametrizing non-projective indecomposable summands of Lie(n), via describing their vertices and sources. Our main result shows that this can be reduced to the case when n is a power of p. When n=9 and p=3, and when n=8 and p=2, we present a precise answer. This suggests a possible parametrization for arbitrary prime powers.Comment: 26 page

The Influence of Hormonal Contraception on Vitamin D Supplementation on Serum 25(OH)D3 Status in Premenopausal Women: A Prospective Double-Blind Placebo Random Controlled Trial

Background: A number of cross-sectional studies have highlighted a potential benefit of estrogen-containing contraception on serum 25-hydroxyvitamin D (25(OH)D) levels. The purpose of the present prospective study was to determine whether oral vitamin D3 supplementation significantly increases serum 25(OH)D more for women taking the estrogen-containing oral contraception than those not taking this medication. Methods: Thirty-eight premenopausal adult females aged 18 - 45 years old were recruited from a university campus; exclusion criteria included those presently taking vitamin D supplementation, those who stopped or started taking oral contraception in last 6 months and those taking any other form of contraception. A prospective doubleblind placebo design was implemented; the dependent variable was serum 25(OH)D and the independent variables were using or not using oral estrogen-containing contraception, and vitamin D3 or placebo supplementation. Participants were tested 4 weeks apart, and blood samples were collected using a capillary blood spot sample method and analyzed by liquid chromatography-tandem mass spectrometry. An independent technician prepared the identical supplement bottles with either 100 placebo pills or 100 active vitamin D3 pills (1,000 IU per pill) and participants randomly selected a supplement bottle. Results: Baseline measurements of 25(OH)D were non-significantly 11% higher in those taking estrogen. ANOVA results revealed a significant two-way interaction between supplementation group (treatment vs. placebo) and treatment period (before vs. after) (P < 0.001), demonstrating a substantial rise in serum 25(OH)D for the treatment group compared with the placebo group. The results also identified a three-way interaction (P = 0.014) on serum 25(OH)D between the three independent variables, with the vitamin D oral contraception group having significantly greater serum 25(OH)D increases (from 45.9 to 98.3 nmol/L) compared with those not taking oral contraception (44.2 - 69.6 nmol/L) (P = 0.019). Conclusions: The estrogen-containing oral contraception increases serum 25(OH)D in premenopausal women with a magnified effect in those taking vitamin D supplementation. Future studies need to examine the relationship between estrogen, vitamin D supplementation, serum 25(OH)D, 1,25(OH)D, parathyroid hormone and other markers of bone metabolisms

The SAMI Galaxy Survey: Global stellar populations on the size-mass plane

We present an analysis of the global stellar populations of galaxies in the SAMI Galaxy Survey. Our sample consists of 1319 galaxies spanning four orders of magnitude in stellar mass and includes all morphologies and environments. We derive luminosity-weighted, single stellar population equivalent stellar ages, metallicities and alpha enhancements from spectra integrated within one effective radius apertures. Variations in galaxy size explain the majority of the scatter in the age--mass and metallicity--mass relations. Stellar populations vary systematically in the plane of galaxy size and stellar mass, such that galaxies with high stellar surface mass density are older, more metal-rich and alpha-enhanced than less dense galaxies. Galaxies with high surface mass densities have a very narrow range of metallicities, however, at fixed mass, the spread in metallicity increases substantially with increasing galaxy size (decreasing density). We identify residual correlations with morphology and environment. At fixed mass and size, galaxies with late-type morphologies, small bulges and low Sersic n are younger than early-type, high n, high bulge-to-total galaxies. Age and metallicity both show small residual correlations with environment; at fixed mass and size, galaxies in denser environments or more massive halos are older and somewhat more metal rich than those in less dense environments. We connect these trends to evolutionary tracks within the size--mass plane.Comment: 25 pages, 18 figures, MNRAS in press Corrected typo in author lis

GNOSIS: the first instrument to use fibre Bragg gratings for OH suppression

GNOSIS is a prototype astrophotonic instrument that utilizes OH suppression fibres consisting of fibre Bragg gratings and photonic lanterns to suppress the 103 brightest atmospheric emission doublets between 1.47-1.7 microns. GNOSIS was commissioned at the 3.9-meter Anglo-Australian Telescope with the IRIS2 spectrograph to demonstrate the potential of OH suppression fibres, but may be potentially used with any telescope and spectrograph combination. Unlike previous atmospheric suppression techniques GNOSIS suppresses the lines before dispersion and in a manner that depends purely on wavelength. We present the instrument design and report the results of laboratory and on-sky tests from commissioning. While these tests demonstrated high throughput and excellent suppression of the skylines by the OH suppression fibres, surprisingly GNOSIS produced no significant reduction in the interline background and the sensitivity of GNOSIS and IRIS2 is about the same as IRIS2. It is unclear whether the lack of reduction in the interline background is due to physical sources or systematic errors as the observations are detector noise-dominated. OH suppression fibres could potentially impact ground-based astronomy at the level of adaptive optics or greater. However, until a clear reduction in the interline background and the corresponding increasing in sensitivity is demonstrated optimized OH suppression fibres paired with a fibre-fed spectrograph will at least provide a real benefits at low resolving powers.Comment: 15 pages, 13 figures, accepted to A

Heritage Quay: What Will You Discover? Transforming the Archives of the University of Huddersfield, Yorkshire, UK

The Heritage Quay project is changing how archive services at the University of Huddersfield are delivered. This article examines how the Staff/Space/Collections dependency model and Customer Service Excellence framework have been used, and what lessons can be drawn for other archives