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Characterisation Of Unresolved Complex Mixtures Of Hydrocarbons, Mark Adrian Gough Jan 1989

Characterisation Of Unresolved Complex Mixtures Of Hydrocarbons, Mark Adrian Gough

School of Geography, Earth and Environmental Sciences Theses

The hydrocarbons of Recent Polluted.., sediments, in-reservoir and laboratory biodegraded crude oils, and certain petroleum products (e. g. lubricating oils) often display "humps" or Unresolved Complex Hixtures (UCHs) when analysed by gas chromatography (CC). Although widespread and often abundant, to date little is known of their detailed molecular composition. Standard chromatographic methods of isolation of model aliphatic and aromatic hydrocarbon UCMs from lubricating oils followed by conventional methods of analysis provided little compositional detail. Thus CC and CC-electron impact mass spectrometry (GC-EIMS) was limited to an estimate of carbon number ranges and to the identification of certain series of *biological …

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Hydrological Conditions In The Region Of Weddel-Scotia Confluence Zone, Gi Shapiro, Me Emelianov Jan 1989

Hydrological Conditions In The Region Of Weddel-Scotia Confluence Zone, Gi Shapiro, Me Emelianov

School of Biological and Marine Sciences

No abstract provided.

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On The Evolution Of Intensive Cyclonic-Anticyclonic Vortex Pairs, Vn Konshin, Gi Shapiro Jan 1989

On The Evolution Of Intensive Cyclonic-Anticyclonic Vortex Pairs, Vn Konshin, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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Ecology Of The Velvet Swimming Crab Liocarcinus Puber (L.) (Brachyura: Portunidae), Christopher Paul Norman Jan 1989

Ecology Of The Velvet Swimming Crab Liocarcinus Puber (L.) (Brachyura: Portunidae), Christopher Paul Norman

School of Biological and Marine Sciences Theses

Currently, Liocarcinus puber is commercially fished in the United Kingdom and exported to Southern Europe. The species appears particularly vulnerable to overfishing and has a history of overexploitation. The present study has examined the reproduction, growth and diet of L. puber, to provide information on which to manage this fishery. Immature Liocarcinus puber were first observed in late summer at a size of 6-10mm long carapace width (LCW). Growth in immature crabs was rapid, and sexual maturity occurred after approx. one year at 45mm (for males) and 40mm (for females) LCW. To differentiate the modal growth of mature crabs, probit …

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Lchthyophthiriasis In Fish: Genetic Variation In Resistance To Infection, Graham Maurice Clayton Jan 1989

Lchthyophthiriasis In Fish: Genetic Variation In Resistance To Infection, Graham Maurice Clayton

School of Biological and Marine Sciences Theses

The frequency and severity of fish diseases is; increasingly, being reported as a limiting factor in the future development of aquaculture. The control of fish disease is largely performed in retrospect through curative chemotherapy. However, the development of resistant strains of fish places the emphasis on preventative, rather than the curative, control of disease. The freshwater parasite Icthyophthirius multifiliis causes the disease known as ichthyophthiriasis or white spot. Losses of fish due to this parasite are believed to total over one million dollars per annum worldwide. The objective of this study was to examine the genetics of resistance to I. …

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The Effect Of Intrathermocline Lenses On Acoustic Fields In The Ocean, Yp Lysanov, Am Plotkin, Gi Shapiro Jan 1989

The Effect Of Intrathermocline Lenses On Acoustic Fields In The Ocean, Yp Lysanov, Am Plotkin, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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On The Forecast Of Lens-Like Eddy Trajectories In The Ocean, Ag Kostianoi, Gi Shapiro Jan 1989

On The Forecast Of Lens-Like Eddy Trajectories In The Ocean, Ag Kostianoi, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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Developmental Changes In The Distribution And Diet Of Nucella Lapillus (L.) From A Mussel Dominated Shore, Jean Harris Jan 1988

Developmental Changes In The Distribution And Diet Of Nucella Lapillus (L.) From A Mussel Dominated Shore, Jean Harris

School of Biological and Marine Sciences Theses

Aspects of the developmental biology of an intertidal predatory gastropod, Nucella lapillus were investigated for a population located on a mussel dominated shore at Whitsand Bay, Cornwall. A field sampling programme revealed that the centre of abundance of small Nucella {<3.4mm) occurred at lower shore levels than that of a larger individuals and the egg capsules. Laboratory studies demonstrated that hatchlings are both negatively geotactic and phototactic, directing than upshore and into crevices.The relative profitabilities of four different sized mussels to four developmental stages of Nucella were investigated using both ability to promote growth and energy gain per unit handling time (E/T) as measures of prey value. The response curves were similar in that proportionately large and small prey were less profitable than medium sized prey with the optimal prey size increasing with predator size. However the most profitable size according to the E/T model was larger than in the growth rate model because large meals appeared to be less efficiently utilized.An ontogenetic- shift in prey size selection was demonstrated in laboratory and field, the results of which were more accurately predicted by the growth rate model of prey value. Predatory events in the field were investigated using borehole dimension as an index of predator size. The feeding and growth of Nucella were investigated at differing periods of tidal emersion. Growth rates were substantially reduced at emersion periods of above 30%, but these could not be wholly attributable to reduced feeding rates. Field growth trials demonstrated that a mature size could be reached in 19-21 months, that growth does not cease at maturity, and that juveniles grow throughout the year. A strong correlation existed between growth rate and environmental temperature. Growth rates in the field were about 75% those in the laboratory, suggesting few constraints on foraging in the field.

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Optimisation In The Life History Of The Hermit Crab Pagurus Bernhardus ( L.), Ian Lancaster Jan 1988

Optimisation In The Life History Of The Hermit Crab Pagurus Bernhardus ( L.), Ian Lancaster

School of Biological and Marine Sciences Theses

Aspects of the ecology of Pagurus bernhardus are examined and the strategies which enable this species to exploit two quite different habitats are determined. The area of shell selection is reviewed and mathematical indices of shell adequacy are rejected as biologically flawed. A subjective index is proposed to more accurately describe the quality of a hermit crab shell resource. Shell preference is considered to be an artificial phenomenon and shell selection is demonstrated to be an essentially random process. Shell-limitation is considered one of the most common problems facing all populations of hermit crabs, detrimentally affecting growth, fecundity, and longevity. …

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The Microstructures Of Estuarine Particles, John Graham Titley Jan 1988

The Microstructures Of Estuarine Particles, John Graham Titley

School of Geography, Earth and Environmental Sciences Theses

A systematic study of the surface properties of suspended and bed sediments from the Tamar Estuary and Restronguet Creek was carried out using a nitrogen adsorption technique. The surface areas and porosities of the particles were determined using BET theory and capillary models applied to the gas adsorption isotherms. The surface areas of the suspended particles collected on axial transects of the Tamar Estuary ranged between 8 and 22 m²/g. The highest values were found for particles in the turbidity maximum region. These appeared to be related in a complex way to both particle size and the chemical composition of …

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Osmoregulation In The Prawn Palaemon Longirostris (Caridea, Palaemonidae), Peter J Campbell Jan 1988

Osmoregulation In The Prawn Palaemon Longirostris (Caridea, Palaemonidae), Peter J Campbell

School of Biological and Marine Sciences Theses

Salinity tolerance, and several aspects of osmoregulation, ionic regulation and permeability were measured for Palaemon longirostris at three temperatures (4, 12 & 20°C). Influence of ontogenetic stage on salinity tolerance and osmoregulation was investigated by testing separately individuals sorted, using carapace length, into 'small' (10-18mm), 'medium' (18-24mm), 'large' (>24mm) and 'ovigerous' (>24mm) size groupings. Effect of seasonal acclimatization on salinity tolerance and osmoregulation was taken into account by comparing responses of summer- with winter-collected prawns. Irrespective of temperature and size, summer Palaemon longirostris were extremely euryhaline and had >90% survival in various salinities from 0.5-34 º/oo . For …

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Protein Synthesis Inhibition And Short And Long Term Habituation Of The Dorsal Antennae Withdrawal Response In Helix Aspersa, Stephen Ray Jan 1988

Protein Synthesis Inhibition And Short And Long Term Habituation Of The Dorsal Antennae Withdrawal Response In Helix Aspersa, Stephen Ray

School of Psychology Theses

The pharmacological disruption of memory by various protein synthesis inhibitory drugs (PSIs) has implicated protein synthesis as a requirement for long term learning but not for short. However, evidence derived from PSI research remains equivocal, with the apparent amnesic effects of PSIs being attributed to drug side-effects and general behavioural debilitations. Research reported in this thesis investigates the behavioural effects on short and long term habituation of the dorsal antennae withdrawal reflex in the snail (Helix aspersa) of three antibiotic drugs known to reversibly inhibit protein synthesis; anisomycin, actinomycin D, and puromycin. Initially, habituation was established as true learning in …

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Evolution Of Rossby Two-Dimensional Solitons Taking Account Of Finite-Amplitude Effect, Vn Konshin, Gi Shapiro Jan 1988

Evolution Of Rossby Two-Dimensional Solitons Taking Account Of Finite-Amplitude Effect, Vn Konshin, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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On The Theory Of Axisymmetric Rossby Solitons, Gi Shapiro Jan 1988

On The Theory Of Axisymmetric Rossby Solitons, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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A Study Of Phagocytosis In Amoebae Of Dictyostelium Discoideum, David Mealing Jan 1987

A Study Of Phagocytosis In Amoebae Of Dictyostelium Discoideum, David Mealing

School of Biological and Marine Sciences Theses

A study has been made of the effects of various treatments on the phagocytosis of 14C-labelled E.coli by amoebae of Dictyostelium discoideum. An assay was also developed for the adhesion of amoebae to glass and the effects of a number of inhibitors on this process have been investigated. The phagocytosis of bacteria was inhibited by chelating agents at millimolar concentrations. The effect of chelators was not apparent in the presence of added divalent cations. However, only a small reduction in cell-glass adhesion was seen with EDTA concentrations that caused large reductions in phagocytosis. The calcium ionophore, A23187 abolished phagocytosis at …

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Immunity In The Alimentary Tract And Other Mucosae Of The Dogfish Scyliorhinus Canicula L., Stephen Hart Jan 1987

Immunity In The Alimentary Tract And Other Mucosae Of The Dogfish Scyliorhinus Canicula L., Stephen Hart

School of Biological and Marine Sciences Theses

The gut of Scyliorhinus canicula was examined by light and electron microscopy and was found to harbour a large and heterogeneous leucocyte population which occupied three niches: the lamina propria (intralaminal leucocytes), the epithelium (intra-epithelial leucocytes) and as accumulations of leucocytes. The lamina propria had a mixed population of cells including three granulocyte types, lymphocytes, plasma cells and macrophages. The epithelium contained a similar spectrum of cells, with the exception of plasma cells, which were only detected in the lamina propria. The lamina propria and epithelium of the gall bladder and reproductive tract also contained leucocytes, although not in the …

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An Investigation Into The Synthesis And Properties Of Some Azafluorenes, Nigel Gordon Smith Jan 1987

An Investigation Into The Synthesis And Properties Of Some Azafluorenes, Nigel Gordon Smith

School of Biological and Marine Sciences Theses

Morphactins are derivatives of 9-hydroxyfluorene-9-carboxylic acid which exhibit plant growth regulating activity. The aim of the work was to synthesise aza analogues (indenopyridines) of these compounds and to assess their biological activity. Additionally, because the chemistry of indenopyridines has received little attention a secondary objective was to extend knowledge in this area. Reviews of the synthesis and reactions of indenopyridine compounds are given.

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The Impact Of Copper In A Contaminated Stream With Particular Reference To Plectrocnemia Conspersa (Curtis) (Trichoptera), Steven Terence Darlington Jan 1987

The Impact Of Copper In A Contaminated Stream With Particular Reference To Plectrocnemia Conspersa (Curtis) (Trichoptera), Steven Terence Darlington

School of Biological and Marine Sciences Theses

An investigation of a copper contaminated mine drainage stream, the Darley Brook, revealed that the water quality was relatively constant over time, with an exceptionally high copper concentration (mean 0.89 mg lˉ¹ ) and low pH (mean 5.2) at its source. Virtually all of the copper was in a 'soluble' form with upto 29% as the free cupric ion. Overall mean leachable copper concentrations of 2139 µg gˉ¹ and 101 µg gˉ¹ were recorded in the uppermost reaches of the Darley Brook and a control stream respectively, with little temporal variation. Biotic communities in the uppermost sampling stations were of …

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Real-Time Detection Of Fronts Utilising In Vivo Phytoplankton Fluorescence Properties, Ceridwen Sally Hatton Jan 1987

Real-Time Detection Of Fronts Utilising In Vivo Phytoplankton Fluorescence Properties, Ceridwen Sally Hatton

School of Biological and Marine Sciences Theses

Historical data suggested that the monitoring of biological parameters might provide a real-time method of predicting the position of ocean fronts (critical to ASV operations). A series of oceanographic surveys was therefore undertaken to investigate the distribution of various parameters (including chlorophyll a (Chl a), nutrients, ATP, and pH) across such fronts. These surveys demonstrated that the continuous monitoring of chlorophyll fluorescence (Chl F) provided the most efficient real-time method for detecting the surface positions of deep-sea, shelf-sea, and shelf-edge fronts (often, in advance of temperature). The rate of change in a parameter (not absolute levels) proved to be critical …

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Studies On The Infection Of Honey Bee Larvae With Ascosphaera Apis, Sally Bamford Jan 1987

Studies On The Infection Of Honey Bee Larvae With Ascosphaera Apis, Sally Bamford

School of Biological and Marine Sciences Theses

The fungus Ascosphaera apis causes the disease chalk brood in larvae of the honey bee, Apis mellifera. Ascospores were recognised as the agents of disease, but the site of their germination to initiate infection had not been established. In this study larval surface cuticle was initially investigated as a possible site, but spores did not even activate here. Therefore, potential inhibitors of spore germination were studied, including water and chloroform washings of larval cuticle; 4 larval food constituents - pollen, honey, brood food, royal jelly; and a variety of medium-chain fatty acids a t concentrations of 1, 0.1 and 0. …

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Synthetic And Biodegradation Studies Of Some Sedimentary Isoprenoid Hydrocarbons, John Nicholas Robson Jan 1987

Synthetic And Biodegradation Studies Of Some Sedimentary Isoprenoid Hydrocarbons, John Nicholas Robson

School of Geography, Earth and Environmental Sciences Theses

Over the past twenty years there have been many published reports of a group of abundant C20, C25 and C30 highly branched acyclic alkanes and alkenes in surface sediments. Synthesis and spectral and chromatographic characterisation of 2,6,10-trimethyl-7-(3-methylbutyl) dodecane (C20), 2,6,10,14-tetramethyl-7-(3-methylpentyl) pentadecane (C25) and 2,6,10,14,18-pentamethyl-7-(3-methylpentyl) nonadecane (C30) in the present study showed that these were the parent skeleta of the unknown hydrocarbons. Only the C20 hydrocarbon has been synthesised previously. Intermediates in the synthetic routes were also fully characterised. The synthetic alkanes and alkenes were used to assign structures to hydrocarbons in several sediments from Europe and Africa and a comprehensive …

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Chemical And Physical Analysis Of Laminated Sediment Formed In Loe Pool, Cornwall, David Alan Pickering Jan 1987

Chemical And Physical Analysis Of Laminated Sediment Formed In Loe Pool, Cornwall, David Alan Pickering

School of Geography, Earth and Environmental Sciences Theses

Laminated and annually-laminated sediments are found in Loe Pool. The origins of such laminations are investigated and evidence for their conditions of formation are presented. In all sediment analysed the combustion residue was greater than 80%, and in the black and grey annually-laminated sediment the organic matter was less than 3%. This indicated that the sediment was dominated by a minerogenic input. The high lacustrine sediment concentrations of copper, zinc and other heavy metals together with evidence from analysis of magnetic variables which indicated high levels of haematite, confirmed that a major sediment source was effluent from mine waste. Analysis …

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The Characteristics Of Synthetic And Natural Hydrous Iron Oxides In Aqueous Environments, Vincent Man Jan 1987

The Characteristics Of Synthetic And Natural Hydrous Iron Oxides In Aqueous Environments, Vincent Man

School of Geography, Earth and Environmental Sciences Theses

The work in this thesis is concerned with the Green Rusts, which are bluegreen metastable Fe(II) - Fe(III) hydroxy compounds incorporating anions such as SO42-, Cl- or CO3-. These Green Rust compounds (or Fe-GR compounds to distinguish them from the aluminium Green Rusts (Al-GRs) which are isostructural Fe(II) - Al(III) hydroxy compounds) can be produced in a consistent fashion from Fe(II) solutions by the method of induced hydrolysis using Fe(III) gel at pH 7 and under anoxic conditions. A series of sulphate and chloride Fe-GR samples were synthesised, and characterised primarily by the analytical techniques of M8ssbauer spectroscopy, X-Ray diffractometry, …

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Sailors' Wives And Husband Absence, Joan Chandler Jan 1987

Sailors' Wives And Husband Absence, Joan Chandler

Other Faculty of Arts, Humanities and Business Theses

This thesis reports on a study of women married to Royal Navy personnel and resident in the West of England and Wales. The analyses are based on data derived from secondary sources, a questionnaire survey and in-depth interviews, the field-work having been conducted between January 1985 and April 1986. Past research has concentrated on the emotional reaction of wives to husband absence, its relationship to anxiety and depression. This thesis is, however, concerned with the social situation of wives intermittently without husbands. It is an exploration of the marital and domestic consequences of husband absence and the implications it has …

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Estuarine Chemical Reactivity At The Particle-Water Interface, Gillian Glegg Jan 1987

Estuarine Chemical Reactivity At The Particle-Water Interface, Gillian Glegg

School of Biological and Marine Sciences Theses

A systematic study of the microstructures of particulate material from the Tamar Estuary using a BET nitrogen adsorption technique has been carried out. The results showed that suspended material had a higher BET surface area (approximately 20m² / g ) than the associated sediments (approximately 13m² / g) . Also the BET surface areas (8-20m² / g) of suspended material collected during axial transects (S = 0-30°/oo) of the Tamar Estuary indicated relatively higher BET surface areas in the turbidity maximum zone as compared to material from up or down estuary. The BET surface areas were inversely related to the …

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The Immune Response In Carp, Cyprinus Carpio L. To Ichthyophthirius Multifiliis, Fouquet 1876, Gillian Houghton Jan 1987

The Immune Response In Carp, Cyprinus Carpio L. To Ichthyophthirius Multifiliis, Fouquet 1876, Gillian Houghton

School of Biological and Marine Sciences Theses

Protective immunity of carp to ichthyophthiriasis has been confirmed, and demonstrated for the first time in juvenile carp, 10-12 weeks old. Standard immunisation procedures were developed here using the theront in preference to cysts. Immunisation included exposure of fish on 3 separate occasions of 14 day intervals to doses of approximately 2,000 theronts per fish, 80/ cm³. Procedures were controlled so that infections were not allowed to continue beyond the primary stage pH (7.0-7.2 ) and temperature (20±2° C) were maintained throughout experimental periods. Four weeks after third immunising dose, fish were exposed to a potentially lethal challenge, approximately 8,000 …

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Some Properties Of Isolated Interthermocline Eddies, Gi Shapiro Jan 1987

Some Properties Of Isolated Interthermocline Eddies, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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On Long-Lived Solitary Eddies In Ocean, Gi Shapiro Jan 1987

On Long-Lived Solitary Eddies In Ocean, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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To The Theory Of Quasigeostrophic Motions Of Finite-Amplitude In The Viscous Stratified Ocean, Gi Shapiro Jan 1987

To The Theory Of Quasigeostrophic Motions Of Finite-Amplitude In The Viscous Stratified Ocean, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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The Behavior Of Organic-Matter In The Area Of The Amazon And Ocean Water Mixing, Ve Artemiev, Gi Shapiro Jan 1987

The Behavior Of Organic-Matter In The Area Of The Amazon And Ocean Water Mixing, Ve Artemiev, Gi Shapiro

School of Biological and Marine Sciences

No abstract provided.

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