• Identification and Genetic Characterisation of Melibiose-Negative Isolates of Streptococcus mutans

      Colby, S.M.; Harrington, Dean J.; Russell, R.R.B. (1995)
      Streptococcus mutans is frequently identified on the basis of phenotypic characteristics such as the ability to ferment carbohydrates. The usefulness of some of these identification tests may be limited in the case of isolates which are atypical with regard to their fermentation properties. We previously identified isolates of S. mutans which were unable to ferment melibiose, a characteristic which is included in some typing schemes. In all of these isolates there was a large chromosomal deletion which included the multiple sugar metabolism (msm) operon which encodes several genes involved in the uptake and metabolism of a number of sugars including melibiose. In the present study, sugar fermentation tests, ribotyping, colony hybridisation with DNA probes and polymerase chain reaction (PCR) were used to investigate the relatedness of these atypical isolates. The PCR and colony hybridisation procedures were based on amplification and detection of two genes: the wapA gene which encodes a surface protein found in all S. mutans strains and the gtfA gene which lies within the msm operon. The colony hybridisation and PCR results confirmed loss of the gtfA gene in the melibiose-negative isolates. Three new melibiose-negative isolates were also identified, but in only 2 of these was the gtfA gene absent, the third did not appear to have lost this region of the chromosome. Biotyping, as well as ribotyping based on an EcoRl digest of chromosomal DNA, revealed that the melibiose-negative isolates fell into a number of distinct groups. The identification of an isolate which is unable to ferment melibiose but does not appear to have lost the msm operon indicates that the melibiose-negative phenotype can arise from more than one type of genetic event.
    • Ten Years in Rehabilitation of Spoil: Appearance, Plant Colonists, and the Dominant Herbivore

      Hambler, David J.; Dixon, Jean M.; Hale, William H.G. (1995)
    • Identity of Streptococcus mutans Surface Protein Antigen III and Wall-Associated Protein Antigen A of Streptococcus mutans

      Russell, M.W.; Harrington, Dean J.; Russell, R.R.B. (1995-02)
      Preparations of Streptococcus mutans surface proteins AgIII and antigen A from different laboratories were compared with regard to amino acid composition, N-terminal amino acid sequence, electrophoretic mobility, and antigenic similarity. Despite previous observations of differences in physical properties, data indicate that these two preparations represent the same protein.
    • Blood Residues on Archaeological Objects - A Conservation Perspective

      Wilson, Andrew S.; Tuross, N.; Wachowiak, M.J. (1996)
    • Excavation of a post-medieval settlement at Druim nan Dearcag, and related sites around Loch Olabhat, North Uist

      Armit, Ian (1997)
      The loch-side settlement of Druim nan Dearcag has been shown by excavation to date to the 16th-17th centuries AD, when it formed part of a dispersed settlement pattern in north-west North Uist. Elements of this settlement system were subsequently truncated by ridge-and-furrow cultivation associated with the cleared township or 'baile' of Foshigarry. The site produced rare structural and artefactual evidence for this period of Hebridean history and may help shed some light on the development of settlement patterns, house types and land use in the late medieval and post-medieval periods.
    • Medieval Painted Vault Rib

      Wilson, Andrew S. (1997)
    • An analysis of the problem of developing environmental education in Brazilian federal protected areas

      De Carvalho, Cristina A.R.; Filho, Walter Leal; Hale, William H.G. (1998)
      This paper describes the problems encountered in developing environmental education in Federal protected areas in Brazil. Results of a survey on the current status of environmental education in four categories of Federal protected areas; namely national parks, biological reserves, ecological stations and environmental protection areas, are described and discussed. The study suggests that the development of environmental education in protected areas in the country has several limitations: financial resources, lack of training, material resources and a lack of policy on environmental education. It also identifies that some of these problems seem to be inter-related with those of the National System of Conservation Units of the country which may result in a retarding of the development of environmental education in such areas.
    • The Degradation of Human Hair Studied by FT-Raman Spectroscopy

      Edwards, Howell G.M.; Farwell, Dennis W.; Wilson, Andrew S. (1998)
    • Re-excavation of an Iron Age wheelhouse and earlier structure at Eilean Maleit, North Uist

      Armit, Ian (1998)
      Excavations were carried out on the tidal islet settlement of Eilean Maleit, previously excavated by Erskine Beveridge in the early part of this century, to test the hypothesis that the site represented a wheelhouse built into an earlier Atlantic roundhouse or broch. It is clear from the re-excavation that the wheelhouse was indeed set into an earlier massive-walled dry stone structure, probably an Atlantic roundhouse but almost certainly not a classic broch tower. The denuded condition of this early structure when the wheelhouse was built suggests that a significant period of time may have elapsed between the occupation of the two structures. Publication of this work is sponsored by Historic Scotland.
    • Local policy for the global environment: In search of a new perspective

      Sharp, Liz (1999)
      British local government is placing a new emphasis on local action for the global environment. In the literature addressing these developments limited attention has been paid to the contested nature of sustainability, or to the local context in which initiatives arise. A cultural politics approach provides a means through which these shortcomings can be overcome (Hajer, 1996). Its discourse basis enables a local authority to be seen as a forum in which technocentric and ecocentric interpretations of sustainability compete with each other, as well as contesting established `non-sustainable¿ approaches. The Foucauldian view of power which underlies cultural politics requires that these contests are viewed in the context of an authority¿s history and traditions. As such, a cultural politics approach could form the basis of a new broader agenda for Local Agenda 21 research.
    • Fourier transform Raman spectroscopy: Evaluation as a non- destructive technique for studying the degradation of human hair from archaeological and forensic environments

      Wilson, Andrew S.; Edwards, Howell G.M.; Farwell, Dennis W.; Janaway, Robert C. (1999)
      Fourier transform (FT) Raman spectroscopy was evaluated as a non-destructive analytical tool for assessing the degradative state of archaeological and forensic hair samples. This work follows the successful application of FT-Raman spectroscopy to studies of both modern hair and ancient keratotic biopolymers, such as mummified skin. Fourteen samples of terminal scalp hair from 13 disparate depositional environments were analysed for evidence of structural alteration. Degradative change was evidenced by alteration to the amide I and III modes near 1651 and 1128 cm−1, respectively, and loss of definition to the (CC) skeletal backbone and the impact of environmental contaminants was noted.
    • Towards a simplified taxonomy of Capsella bursa-pastoris (L.) Medik. (Brassicaceae)

      Aksoy, A.; Hale, William H.G.; Dixon, Jean M. (1999)
      Capsella bursa-pastoris (L.) Medik. is a species with a cosmopolitan distribution which shows considerable morphological variation. Numerous authors have recognised widely differing numbers of varieties, microspecies or other infraspecific subdivisions (segregates) of this species. In an attempt to clarify this situation, we grew British material of the species under controlled conditions through to the F) generation to remove environmental variation, and assessed the plants on the basis of a range of morphological criteria, namely leaf shape, capsule size and also length of time taken to flower. Analysis of these characteristics consistently produced four basic groups, which had been previously described. Herbarium specimens could also nearly always be assigned to one of these groups. Limited chromosome counts suggest that two of these groups are diploid and two are tetraploid. We suggest this fourfold division into broad groups reflects the major genetic separations within the species, but that there is also considerable phenotypic plasticity shown by C. bursapastoris in response to factors such as shade or trampling. These four groups appear to differ in their geographic.al distribution in Britain. KEYWORDS: Shepherd's Purse, morphological variation, leaf characters, capsule characters, chromosome
    • Capsella bursa-pastoris (L.) Medic. as a biomonitor of heavy metals

      Aksoy, A.; Hale, William H.G.; Dixon, Jean M. (1999)
    • A Later Bronze Age Shield from South Cadbury, Somerset, England

      Coles, J.M.; Leach, P.; Minnitt, S.C.; Tabor, R.; Wilson, Andrew S. (1999)
      A shield of beaten bronze from South Cadbury, Somerset, England is the first shield to be discovered by excavation on an archaeological site. The shield lay in a silt-filled Bronze Age ditch on a spur of land below Cadbury Castle. A stake was thrust through the shield. The paper considers the recovery and conservation of the shield, the technology of metal shields and the evidence for the ritual deposition of shields in the Later Bronze Age of western Europe.
    • The abandonment of souterrains: evolution, catastrophe or dislocation?

      Armit, Ian (1999)
      This paper considers the evidence for the abandonment of souterrains in that part of east central Scotland characterized by Wainwright as 'southern Pictland'. The evidence suggests that most souterrains here were deliberately destroyed, or at least infilled, and that none seems to have outlasted the early third century AD. The process of destruction seems to have been associated with a significant degree of ritual activity not previously noted. It is postulated that the evidence would allow for a single episode of abandonment (a 'souterrain abandonment horizon'), in the late second or early third century AD, which might be related to a major reorientation of social and political structures, perhaps associated with changes in Roman frontier policy.