2,028 research outputs found

    A freemartin calf with XX /XXY mosaicism

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    Mapping Henry: Dendrochronological Analysis of a Sixteenth-Century Panel Painting Based Upon Synchrotron-Sourced X-ray Fluorescence Mapping

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    The study of materials that comprise artworks significantly contributes to understanding of age and provenance. While dendrochronology is a particularly valuable and well-established technique for panel paintings comprising oak timber, conventional practices of resurfacing end-grains to reveal tree rings is becoming less acceptable because it removes material, modifying the painting. Recently, application of non-destructive X-ray fluorescence (XRF) spectroscopy to a portrait of Henry VIII held by the Art Gallery of New South Wales (AGNSW), Sydney, Australia revealed tree-ring boundaries in the resulting high-resolution elastic scatter XRF map. In this study, we examine the dendrochronological potential of that mapping with the aim of contributing to resolving the relationship of the AGNSW portrait to similar paintings elsewhere. Examination of the timber revealed affinities with Quercus petraea (Matt.). We measured tree-ring widths along multiple paths in the XRF scatter map and crossdated the resulting 81-year XRF ring-width (XRF portrait ) series against master chronologies of English, western European, and Baltic origin. Rather than an arbitrarily defined threshold, we used a Bonferroni correction to determine a minimum significance level for crossdating. While the XRF portrait series did not crossdate with the continental European chronologies, we identified a single significant (α = 3.4 × 10−6) dating position with the English chronology (1400–1480 CE). Cross-matching with site-level chronologies revealed a cluster of high t-values in central-southern England. The earliest date of felling precedes the documented date of completion for the AGNSW and two similar Tudor portraits of Henry VIII held by the National Portrait Gallery (NPG), London and one at the Society of Antiquaries, London. While the apparent British provenance of timber used in the AGNSW portrait contrasts to Baltic origin of timbers used for the two NPG portraits and the majority of English panel paintings, it is consistent with the provenance of the timber used for the Society of Antiquaries portrait

    Technical assistance, neo-colonialism or mutual trade? The experience of an Anglo/Ukrainian/Russian social work practice learning project

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    Since the collapse of the Soviet Union there has been a steady stream of Western consultants ready to work in Eastern Europe and Russia and share professional and academic expertise and experience. Social work, unknown as a discrete discipline or profession in the Soviet Union, has been a growth area with funding from a variety of sources to help promote East-West partnerships.Social work theory and practice emphasises critical appraisal of policy and embraces issues of power, discrimination and oppression. Social work educators should therefore be especially alert to the complex ethical questions which these kinds of collaborations raise, and adept at finding practical solutions or workable compromises. This article explores these ethical and political issues with reference to a project to develop social work practice learning in a Russian oblast' (region). The project was an ambitious partnership of British, Ukrainian and Russian educators, involving numerous Russian social work and related agencies, and four Russian universities and colleges in one oblast'. The authors use a series of vignettes to help the reader achieve insights into these East-West transactions. The article concludes with a discussion of different interpretations of these dealings, using three prisms: technical assistance, neo-colonialism and mutual trade

    Heterologous prime-boost-boost immunisation of Chinese cynomolgus macaques using DNA and recombinant poxvirus vectors expressing HIV-1 virus-like particles

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    Background: There is renewed interest in the development of poxvirus vector-based HIV vaccines due to the protective effect observed with repeated recombinant canarypox priming with gp120 boosting in the recent Thai placebo-controlled trial. This study sought to investigate whether a heterologous prime-boost-boost vaccine regimen in Chinese cynomolgus macaques with a DNA vaccine and recombinant poxviral vectors expressing HIV virus-like particles bearing envelopes derived from the most prevalent clades circulating in sub-Saharan Africa, focused the antibody response to shared neutralising epitopes. Methods: Three Chinese cynomolgus macaques were immunised via intramuscular injections using a regimen composed of a prime with two DNA vaccines expressing clade A Env/clade B Gag followed by boosting with recombinant fowlpox virus expressing HIV-1 clade D Gag, Env and cholera toxin B subunit followed by the final boost with recombinant modified vaccinia virus Ankara expressing HIV-1 clade C Env, Gag and human complement protein C3d. We measured the macaque serum antibody responses by ELISA, enumerated T cell responses by IFN-gamma ELISpot and assessed seroneutralisation of HIV-1 using the TZM-bl beta-galactosidase assay with primary isolates of HIV-1. Results: This study shows that large and complex synthetic DNA sequences can be successfully cloned in a single step into two poxvirus vectors: MVA and FPV and the recombinant poxviruses could be grown to high titres. The vaccine candidates showed appropriate expression of recombinant proteins with the formation of authentic HIV virus-like particles seen on transmission electron microscopy. In addition the b12 epitope was shown to be held in common by the vaccine candidates using confocal immunofluorescent microscopy. The vaccine candidates were safely administered to Chinese cynomolgus macaques which elicited modest T cell responses at the end of the study but only one out of the three macaques elicited an HIV-specific antibody response. However, the antibodies did not neutralise primary isolates of HIV-1 or the V3-sensitive isolate SF162 using the TZM-bl b-galactosidase assay. Conclusions: MVA and FP9 are ideal replication-deficient viral vectors for HIV-1 vaccines due to their excellent safety profile for use in humans. This study shows this novel prime-boost-boost regimen was poorly immunogenic in Chinese cynomolgus macaques

    Unbiased Cosmological Parameter Estimation from Emission Line Surveys with Interlopers

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    The galaxy catalogs generated from low-resolution emission line surveys often contain both foreground and background interlopers due to line misidentification, which can bias the cosmological parameter estimation. In this paper, we present a method for correcting the interloper bias by using the joint-analysis of auto- and cross-power spectra of the main and the interloper samples. In particular, we can measure the interloper fractions from the cross-correlation between the interlopers and survey galaxies, because the true cross-correlation must be negligibly small. The estimated interloper fractions, in turn, remove the interloper bias in the cosmological parameter estimation. For example, in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) low-redshift (z<0.5z<0.5) [O II] λ3727\lambda3727{\AA} emitters contaminate high-redshift (1.9<z<3.51.9<z<3.5) Lyman-α\alpha line emitters. We demonstrate that the joint-analysis method yields a high signal-to-noise ratio measurement of the interloper fractions while only marginally increasing the uncertainties in the cosmological parameters relative to the case without interlopers. We also show the same is true for the high-latitude spectroscopic survey of Wide-Field Infrared Survey Telescope (WFIRST) mission where contamination occurs between the Balmer-α\alpha line emitters at lower redshifts (1.1<z<1.91.1<z<1.9) and Oxygen ([O III] λ5007\lambda5007{\AA}) line emitters at higher redshifts (1.7<z<2.81.7<z<2.8).Comment: 36 pages, 26 figure

    Constructing a WISE High Resolution Galaxy Atlas

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    After eight months of continuous observations, the Wide-field Infrared Survey Explorer (WISE) mapped the entire sky at 3.4 {\mu}m, 4.6 {\mu}m, 12 {\mu}m and 22 {\mu}m. We have begun a dedicated WISE High Resolution Galaxy Atlas (WHRGA) project to fully characterize large, nearby galaxies and produce a legacy image atlas and source catalogue. Here we summarize the deconvolution technique used to significantly improve the spatial resolution of WISE imaging, specifically designed to study the internal anatomy of nearby galaxies. As a case study, we present results for the galaxy NGC 1566, comparing the WISE super-resolution image processing to that of Spitzer, GALEX and ground-based imaging. The is the first paper in a two part series; results for a much larger sample of nearby galaxies is presented in the second paper.Comment: Published in the AJ (2012, AJ, 144, 68
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