228 research outputs found

    In search of the Northern Britons in the Early Historic Era (AD 400–1100)

    Get PDF
    This is part of the series Resource Assessment of Local History and Archaeology in West Central Scotland, commissioned for the Regional Framework for Local History and Archaeology,a partnership project led by Glasgow Museums. This paper offers a personal perspective on the key research themes relating to the Northern Britons, who are the most obscure inhabitants of Dark Age Scotland. It includes an overview of the fragmented historical legacy of the Britons, which is essential for appreciating their cultural contribution to the making of Scotland and for identifying research priorities. A detailed review of archaeological investigations in the study area is beyond the scope of this paper, so emphasis is focused on recent work which relates to three broad areas identified for future research: secular settlement, church archaeology and political development

    Doors to different worlds: conceptual connections between Gotlandic and Pictish sculpture

    Get PDF
    Argues that Pictish cross-slabs are intended to represent church doorways following a parallel example of such imagery from Gotland proposed by Anders Andrén

    Dossier on Govan Young: Exploring children’s historical consciousness through film and archaeology

    Get PDF
    Govan Young (2017) is a 30-minute documentary in which schoolchildren from Glasgow learn of the area’s important but largely unknown medieval history. This dossier brings together four essays that reflect on the film from various academic perspectives – film studies, archaeology and education – to explore how schoolchildren might learn about the past, and develop a historical consciousness, by participating in film-making projects. The dossier also reflects on how educators can learn from those whom they are supposedly teaching, thereby highlighting that experimental pedagogical projects often bring unexpected learning outcomes into being. Consequently, educators must resist the pressures to predict the outcomes of projects, and must strive to keep the future open-ended

    Dissolution of wollastonite during the experimental manipulation of Hubbard Brook Watershed 1

    Full text link
    Powdered and pelletized wollastonite (CaSiO 3 ) was applied to an 11.8 ha forested watershed at the Hubbard Brook Experimental Forest (HBEF) in northern New Hampshire, U.S.A. during October of 1999. The dissolution of wollastonite was studied using watershed solute mass balances, and a 87 Sr/ 86 Sr isotopic tracer. The wollastonite ( 87 Sr/ 86 Sr = 0.70554) that was deposited directly into the stream channel began to dissolve immediately, resulting in marked increases in stream water Ca concentrations and decreases in the 87 Sr/ 86 Sr ratios from pre-application values of 0.872 mg/L and 0.72032 to values of ∼2.6 mg/L and 0.71818 respectively. After one calendar year, 401 kg of the initial 631 kg of wollastonite applied to the stream channel was exported as stream dissolved load, and 230 kg remained within the stream channel as residual CaSiO 3 and/or adsorbed on streambed exchange sites. Using previously established values for streambed Ca exchange capacity at the HBEF, the dissolution rate for wollastonite was found to be consistent with dissolution rates measured in laboratory experiments. Initially, Ca was released from the mineral lattice faster than Si, resulting in the development of a Ca-depleted leached layer on mineral grains. The degree of preferential Ca release decreased with time and reached stoichiometric proportions after ∼6 months. Using Sr as a proxy for Ca, the Ca from wollastonite dissolution can be accurately tracked as it is transported through the aquatic and terrestrial ecosystems of this watershed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42477/1/10533_2004_Article_5118334.pd

    Progress report no. 5

    Get PDF
    Includes bibliographical referencesProgress report; June 30, 1974U.S. Atomic Energy Commission contract AT(11-1)225

    Genomic Legacy of the African Cheetah, Acinonyx jubatus

    Get PDF
    Background Patterns of genetic and genomic variance are informative in inferring population history for human, model species and endangered populations. Results Here the genome sequence of wild-born African cheetahs reveals extreme genomic depletion in SNV incidence, SNV density, SNVs of coding genes, MHC class I and II genes, and mitochondrial DNA SNVs. Cheetah genomes are on average 95 % homozygous compared to the genomes of the outbred domestic cat (24.08 % homozygous), Virunga Mountain Gorilla (78.12 %), inbred Abyssinian cat (62.63 %), Tasmanian devil, domestic dog and other mammalian species. Demographic estimators impute two ancestral population bottlenecks: one \u3e100,000 years ago coincident with cheetah migrations out of the Americas and into Eurasia and Africa, and a second 11,084–12,589 years ago in Africa coincident with late Pleistocene large mammal extinctions. MHC class I gene loss and dramatic reduction in functional diversity of MHC genes would explain why cheetahs ablate skin graft rejection among unrelated individuals. Significant excess of non-synonymous mutations in AKAP4 (p\u3c0.02), a gene mediating spermatozoon development, indicates cheetah fixation of five function-damaging amino acid variants distinct from AKAP4 homologues of other Felidae or mammals; AKAP4 dysfunction may cause the cheetah’s extremely high (\u3e80 %) pleiomorphic sperm. Conclusions The study provides an unprecedented genomic perspective for the rare cheetah, with potential relevance to the species’ natural history, physiological adaptations and unique reproductive disposition

    Structure of a Murine Norovirus NS6 Protease-Product Complex Revealed by Adventitious Crystallisation

    Get PDF
    Murine noroviruses have emerged as a valuable tool for investigating the molecular basis of infection and pathogenesis of the closely related human noroviruses, which are the major cause of non-bacterial gastroenteritis. The replication of noroviruses relies on the proteolytic processing of a large polyprotein precursor into six non-structural proteins (NS1–2, NS3, NS4, NS5, NS6pro, NS7pol) by the virally-encoded NS6 protease. We report here the crystal structure of MNV NS6pro, which has been determined to a resolution of 1.6 Å. Adventitiously, the crystal contacts are mediated in part by the binding of the C-terminus of NS6pro within the peptide-binding cleft of a neighbouring molecule. This insertion occurs for both molecules in the asymmetric unit of the crystal in a manner that is consistent with physiologically-relevant binding, thereby providing two independent views of a protease-peptide complex. Since the NS6pro C-terminus is formed in vivo by NS6pro processing, these crystal contacts replicate the protease-product complex that is formed immediately following cleavage of the peptide bond at the NS6-NS7 junction. The observed mode of binding of the C-terminal product peptide yields new insights into the structural basis of NS6pro specificity

    Highly Volcanic Exoplanets, Lava Worlds, and Magma Ocean Worlds:An Emerging Class of Dynamic Exoplanets of Significant Scientific Priority

    Get PDF
    Highly volcanic exoplanets, which can be variously characterized as 'lava worlds', 'magma ocean worlds', or 'super-Ios' are high priority targets for investigation. The term 'lava world' may refer to any planet with extensive surface lava lakes, while the term 'magma ocean world' refers to planets with global or hemispherical magma oceans at their surface. 'Highly volcanic planets', including super-Ios, may simply have large, or large numbers of, active explosive or extrusive volcanoes of any form. They are plausibly highly diverse, with magmatic processes across a wide range of compositions, temperatures, activity rates, volcanic eruption styles, and background gravitational force magnitudes. Worlds in all these classes are likely to be the most characterizable rocky exoplanets in the near future due to observational advantages that stem from their preferential occurrence in short orbital periods and their bright day-side flux in the infrared. Transit techniques should enable a level of characterization of these worlds analogous to hot Jupiters. Understanding processes on highly volcanic worlds is critical to interpret imminent observations. The physical states of these worlds are likely to inform not just geodynamic processes, but also planet formation, and phenomena crucial to habitability. Volcanic and magmatic activity uniquely allows chemical investigation of otherwise spectroscopically inaccessible interior compositions. These worlds will be vital to assess the degree to which planetary interior element abundances compare to their stellar hosts, and may also offer pathways to study both the very young Earth, and the very early form of many silicate planets where magma oceans and surface lava lakes are expected to be more prevalent. We suggest that highly volcanic worlds may become second only to habitable worlds in terms of both scientific and public long-term interest.Comment: A white paper submitted in response to the National Academy of Sciences 2018 Exoplanet Science Strategy solicitation, from the NASA Sellers Exoplanet Environments Collaboration (SEEC) of the Goddard Space Flight Center. 6 pages, 0 figure

    Automated High-Content Live Animal Drug Screening Using C. elegans Expressing the Aggregation Prone Serpin α1-antitrypsin Z

    Get PDF
    The development of preclinical models amenable to live animal bioactive compound screening is an attractive approach to discovering effective pharmacological therapies for disorders caused by misfolded and aggregation-prone proteins. In general, however, live animal drug screening is labor and resource intensive, and has been hampered by the lack of robust assay designs and high throughput work-flows. Based on their small size, tissue transparency and ease of cultivation, the use of C. elegans should obviate many of the technical impediments associated with live animal drug screening. Moreover, their genetic tractability and accomplished record for providing insights into the molecular and cellular basis of human disease, should make C. elegans an ideal model system for in vivo drug discovery campaigns. The goal of this study was to determine whether C. elegans could be adapted to high-throughput and high-content drug screening strategies analogous to those developed for cell-based systems. Using transgenic animals expressing fluorescently-tagged proteins, we first developed a high-quality, high-throughput work-flow utilizing an automated fluorescence microscopy platform with integrated image acquisition and data analysis modules to qualitatively assess different biological processes including, growth, tissue development, cell viability and autophagy. We next adapted this technology to conduct a small molecule screen and identified compounds that altered the intracellular accumulation of the human aggregation prone mutant that causes liver disease in α1-antitrypsin deficiency. This study provides powerful validation for advancement in preclinical drug discovery campaigns by screening live C. elegans modeling α1-antitrypsin deficiency and other complex disease phenotypes on high-content imaging platforms
    corecore