Southwest UK Research Articles

Geographical variation in species diversity: A comparison of marine polychaetes and nematodes

The aim of this study was to determine if marine species diversity was influenced by geographical location and whether it was higher at lower latitudes. Artificial collectors (made of nylon pan scourers) were employed as a standard substratum for the colonisation of marine invertebrates inhabiting subtidal (12 to 15 m) hard, rocky bottom substrata. These artificial substrate units (ASUs) were deployed at different latitudes including northern and southern temperate (South West England, UK and New Zealand), tropical (Trinidad and Tobago, West Indies) and polar (Signy Island, Antarctica) areas. The polychaetes, representative of the macrofauna and the nematodes, representative of the meiofauna fractions of the total invertebrate fauna collected were analysed. Neither polychaete nor nematode species diversity showed a trend based on latitude and each taxon showed a different pattern of diversity variation in relation to location. Polychaete diversity varied from area to area with highest species diversity occurring in the southern temperate (New Zealand). Nematode species diversity however was similar for the northern and southern temperate (UK and New Zealand) and the tropical area (Trinidad and Tobago). Thus, although the number of locations studied was limited, these data do not conform to a gradient in species diversity with latitude as has been previously supposed. The success of ASUs to compare species diversities in standardised habitat units augurs well for their future use in other ecological areas such as biogeographical or pollution studies.

RESETTLED REFUGEES: Refugees, Transition and Employment Prospects in Plymouth and the South West Uk

RESETTLED REFUGEES: Refugees, Transition and Employment Prospects in Plymouth and the South West Uk

A pragmatic approach to dosimetric audit in radiotherapy.

In 1993 a dosimetric audit programme was initiated by physicists from a group of hospitals in the South West UK with the aim of detecting dosimetric errors greater than 5%. The scope of this programme was developed to cover megavoltage and kilovoltage photons as well as electrons. Procedures operated within each department were also audited in situations where they could influence dosimetry. No dose discrepancies greater than 5% were detected in the course of the audits, though differences did correlate with complexity in some situations. These measurements provide an ongoing assurance that dosimetry within the participating centres is well controlled and provides a firm foundation for clinical practice.

Delayed prescribing of antibiotics increased duration of acute otitis media symptoms in children but reduced diarrhoea

Design Randomised (unclear allocation concealment), unblinded, controlled trial with about 1 week of follow up. Setting General practices in south west UK. Patients 315 children aged 6 months to 10...

Robertsonian polymorphism in the marine gastropod, Nucella lapillus: advances in karyology using rDNA loci and NORs

Previous studies of the Robertsonian polymorphism in the Atlantic dog-whelk, Nucella lapillus (2n = 26-36), have been limited by the inability to identify unequivocally individual chromosomes in the karyotype. This species, as with many other marine invertebrates, has proven largely refractory to the standard (mammalian) chromosome-banding techniques. In this study, fluorescence in situ hybridization (FISH) using a rDNA probe was applied to the metaphase chromosomes of the 2n = 26 and 2n = 36 forms of N. lapillus. The results were compared with silver-staining of the nucleolar organizer regions (NORs). The FISH technique was shown to be more sensitive and less intrinsically prone to variation than the silver-staining method. An additional NOR/rDNA locus was observed in the 2n = 36 form which, to date, has not been seen in any 2n = 26 population. The 2n = 36 karyotype is described for a south-west UK population that differs from that reported previously in the literature. After fission, Robertsonian metacentrics are shown to correspond to at least one subtelocentric product.