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Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon Jan 1998

Trace Metal-Particle Water Interactions In The Western North Sea, Joanna Dixon

School of Geography, Earth and Environmental Sciences Theses

The distribution of trace metals (Fe, Mn, Cu, Cd and Pb) has been determined in dissolved and particulate phases, along with relevant hydrographic parameters, from the nearshore coastal zone of the western North Sea (between 52ON and 56ON) during four Land Ocean Interaction Study (LOIS) surveys covering the seasonal cycle (autumn 1994 to summer 1995) The behaviour of the redox-sensitive metals, Fep and Mnp in the western North Sea were strongly correlated (r>0 44 for all seasons, P<0 05) in all surveys and exhibited maximum concentrations in winter (16 mg g -1 and 700 ug g-1 respectively) which progressively decreased throughout the year Distinct seasonal variations were also observed for particulate Cu, Cd and Pb For example, enhanced concentrations of Cup (36 ± 39 ug g-1) and Cdp (0.36 ± 0.42 ug g -1) in the Humber coastal zone during summer were attributed to preferential particulate organic/biogenic-metal interactions. In contrast enhanced, though diffuse, atmospheric inputs of Pb from continental winds were considered to have contributed to the elevated Pbp concentrations (82 ± 27 ug g -1) observed offshore during winter Results from radiotracer incubation experiments suggest that biological activity makes a significant contribution to the removal of dissolved Mn and Cd to the particulate phase. However, a phase lag of two to three months between maximum primary productivity and maximum particulate metal adsorption (KD=2 X 104 & 5 x 102 for Mn and Cd respectively) indicates a decoupling from the spring plankton bloom In general metal distributions in the Humber coastal zone were significantly influenced by freshwater discharge, tidal regime at the mouth of the estuary and prevailing wind conditions Total trace metal fluxes across the mouth of the Humber Estuary were highest during spring (311, 8 96 & 1045 kg day-1, for Cu, Cd and Pb respectively) and lowest during summer (25 7, 1 .12 & 33 4 kg day-1, for Cu, Cd and Pb respectively) They were dominated by variations in freshwater outflow and the tidal range during sampling On an annual basis comparison to estuarine inputs (rivers, industry and sewage sources) suggested retention of Cu (25%) and Cd (56%) Estimates of partitioning (KD) were derived from the dissolved and particulate data for Cu, Cd and Pb over the seasonal cycle Copper was dominated by the particulate phase (73-80%) in all seasons but summer, whilst Cd showed particulate phase dominance (54-70%) in autumn and winter only The Pb distributions were dominated by the particulate phase (94-99%) independent of season Trace metal settling velocities implied that the Humber Plume was acting as a sink for Cu, Cd and Pb in winter and spring However settling velocities calculated for Cd and Pb (flood tide) in summer were similar to background suspended particulate matter (SPM) suggesting long range transport with the residual circulation. Modelling of Pb isotopic ratios in the Humber Plume suggested that on average 32-39% of the extracted Pbp originated from anthropogenic sources The data from this study has given unique information concerning the concurrent seasonal distributions of particulate trace metals in the western North Sea and have yielded new insights into mechanisms affecting trace metal cycling and transport, essential in the development and refinement of coupled hydrodynamic-geochemical models.

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Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor Jan 1998

Development Of A Low Pressure-Inductively Coupled Plasma-Ion Source For Mass Spectrometry, Gavin Thomas O'Connor

School of Geography, Earth and Environmental Sciences Theses

A low pressure-inductively coupled plasma (LP-ICP) ion source has been investigated for the production of atomic and molecular ions for mass spectrometry (MS). A dedicated LPICP- MS was constructed, by modifying a Hewlett Packard mass selective detector, to detect ions from the LP-ICP. The ion sampling interface and ion optics were designed using established theory and the use of a computer simulation program. Perfluorotributylamine was continuously introduced into the LP-ICP, via a molecular leak, and the ion sampling interface, plasma forward power, and plasma gas flow rates, were optimised. When the LP-ICP ion source was sustained at 6W with a …

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Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat Jan 1998

Modelling And Monitoring Of Phosphorus Transport And Speciation In Soil, Darren Michael William Peat

School of Geography, Earth and Environmental Sciences Theses

Flow through soil into groundwater has been classically conceptualised as taking place through a set of aligned capillary tubes. In solute transport models these approximations are also present. Pore-Cor (a network model) has been used to model the void structure of soil by using water retention and mercury porosimetry curves. The model successfully predicts trends in saturated hydraulic conductivity. The effect of the assumptions used in the Pore-Cor geometry have been investigated by comparing of two dimensional slices of the simulated networks with two dimensional image analysis data. The geometric limitations of the model cause packing inefficiencies which prevent the …

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Particle-Water Interactions Of Hydrophobic Organic Micropollutants In Marine Systems, M. Carl Rawling Jan 1998

Particle-Water Interactions Of Hydrophobic Organic Micropollutants In Marine Systems, M. Carl Rawling

School of Geography, Earth and Environmental Sciences Theses

An understanding of the reactivity of hydrophobic organic micropollutants (HOMs) is of paramount importance to water quality managers because of their toxicity, persistence, and liability to bioaccumulate. In this study, the role played by the main estuarine variables (organic matter, suspended particulate matter [SPM], particle type and salinity) on HOM behaviour was investigated by employing samples from estuaries with different geochemical signatures (Chupa, Russia, and the Dart, Plym, Beaulieu and Carnon, U K ) . A laboratory-based technique was developed for the determination of the solubility and sorptive behaviour of HOMs using 14C-labelled, beta-emitting organic compounds (2,2\5,5'-tetrachlorobiphenyl (2,2’5,5'-TCB), bis(2-ethylhexyl)phthalate ester …

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In-Situ Preconcentration Of Trace Metals In Natural Waters And Brines With Analysis By Flow Injection Atomic Spectrometry, Robert Anthony Nickson Jan 1998

In-Situ Preconcentration Of Trace Metals In Natural Waters And Brines With Analysis By Flow Injection Atomic Spectrometry, Robert Anthony Nickson

School of Geography, Earth and Environmental Sciences Theses

Atomic spectrometric techniques such as ICP-MS offer exceptional sensitivity and multi-element capability for trace metal analysis but the formation of polyatomic ions (particularly below m/z = 80) can cause serious interferences. Such interfering species may be introduced via precursor atoms in atmospheric gases, the sample matrix or impurities in the reagents and gases. There is an environmental need to establish rapid multi-element methods of analysis for trace metals in environmental waters and the subsequent speciation of these trace elements. Natural waters, particularly those with a high dissolved solids content such as sea water are difficult to analyse directly by ICP …

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On-Line Sample Pretreatment Of Environmental Samples For Use With Atomic Spectrometry, James Robert Murphy Jan 1998

On-Line Sample Pretreatment Of Environmental Samples For Use With Atomic Spectrometry, James Robert Murphy

School of Geography, Earth and Environmental Sciences Theses

The objective of this study was to develop novel techniques for on-line sample pre-treatment for use with atomic spectroscopy. Preconcentration of the analytes using either complexation of the analyte(s) on an analytical column or by in-situ (in atomiser) trapping on a pre-coated graphite tube has been used. The samples were manipulated using flow injection analysis and detection achieved in most cases by ETAAS. All aspects of the study are supported by reference to the literature. Using the above approach, a new method has been developed to determine mercury in environmental (sediment) and biological (tuna fish) samples. This approach successfully achieved …

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Isolation And Characterisation Of Immunoglobulin Gene Superfamily Molecules From Lower Vertebrates (Fish), Bingmei Yang Jan 1998

Isolation And Characterisation Of Immunoglobulin Gene Superfamily Molecules From Lower Vertebrates (Fish), Bingmei Yang

Other Faculty of Health Theses

Acquired immunity in vertebrates is a major mechanism of the immune system, which enables the vertebrates to discriminate self and non-self The most important feature of acquired immunity is the major histocompatibility complex (MHC) restricted-cellular immune response. This involves several important elements including MHC molecules and T cell antigen receptor (TCR) complex. MHC molecules are glycoproteins that recognise and present self and foreign peptides to T-cells via the TCR, causing the T cell to proliferate and secrete cytokines. There is increasing evidence that peripheral T cells and MHC restricted cellular immune responses occur in all vertebrates. However, the exact nature …

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The Effect Of Sea Weed (Ascophyllum Nodosum) Extract On Antioxidant Activities And Drought Tolerance Of Tall Fescue (Festuca Arundinacea Schreb.), Jamal Yousef Ayad Jan 1998

The Effect Of Sea Weed (Ascophyllum Nodosum) Extract On Antioxidant Activities And Drought Tolerance Of Tall Fescue (Festuca Arundinacea Schreb.), Jamal Yousef Ayad

Other Faculty of Science and Engineering Theses

Plants have developed enzymatic and nonenzymatic antioxidant mechanisms to prevent oxidation of cellular compartments. Enhancing these mechanisms might help plants cope with encountered stresses. Greenhouse and field studies were conducted to examine the influence of seaweed (Ascophyllum nodosum) extract on antioxidant enzymes activities, forage Growth, and persistence of tall fescue (Festuca arundinacea Schreb.). Furthermore. effects of soil moisture, plant genotype, and infection with the endophyte Neotyphodium coenophialum ([Morgan-Jones and Gams] Glenn, Bacon and Hanlin) were investigated. In a greenhouse experiment, seaweed extract was applied to ‘Martin’ tall fescue at 0, 2, 4, 6, 8, and 10 kg ha in a …

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Behaviour, Welfare And Nutrition Of Group-Housed Sows Fed In An Electronic Sow Feeding System, Nicola Jane Hodgkiss Jan 1998

Behaviour, Welfare And Nutrition Of Group-Housed Sows Fed In An Electronic Sow Feeding System, Nicola Jane Hodgkiss

Other Faculty of Science and Engineering Theses

A programme of study was undertaken to assess the welfare status of multiparous gestating sows housed in dynamic groups in a straw yard and fed by electronic sow feeders (ESF).Comparison of production figures from the Seale-Hayne herd with those nationally confirmed its status as a typical commercial unit. In an initial series of investigations, detailed ethograms were compiled to describe the animals' repertoire of activities and interactions. Lying and straw manipulation were found to be the predominant behaviours and attacks directed towards the head were the most commonly performed type of interaction. Although there was little evidence of aggressive behaviour, …

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Free Radical Activity, Lipid Peroxidation And Antioxidant Status In Diabetes Mellitus, Irena Christine Belka Jan 1998

Free Radical Activity, Lipid Peroxidation And Antioxidant Status In Diabetes Mellitus, Irena Christine Belka

Other Faculty of Health Theses

The role of free radicals and antioxidants in human disease, particularly cardiovascular disease is an area of intensive research. Diabetes mellitus is the most common condition associated with increased oxidative stress and accelerated atherosclerosis. Increased levels of lipid peroxides and diminished antioxidant vitamin status have been reported in diabetic patients and are also implicated in the chronic complications of diabetes. The autoxidation and glycoxidation reactions of glucose are sources of free radicals in vitro and a preliminary investigation that these reactions may be a source of free radicals in vivo was undertaken in patients admitted to hospital with severe hyperglycaemia …

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The Influence Of Nitrification In Determining The Supply, Distribution And Fate Of Nitrogen In Grassland Soils, David John Hatch Jan 1998

The Influence Of Nitrification In Determining The Supply, Distribution And Fate Of Nitrogen In Grassland Soils, David John Hatch

Other Faculty of Science and Engineering Theses

The microbiology of nitrification has been extensively studied, but the ecology and environmental impact of the process has received less attention. The reason for this has more to do with the difficulties of conducting field experiments to examine the links with other processes which cause losses of nitrogen, than a failure to appreciate its importance in agricultural systems. This project was designed to overcome some of the limitations of existing field techniques to enable simultaneous measurements of nitrification and the major processes of N supply (mineralization) and N loss (denitrification and leaching) to be examined. The study proceeded in three …

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Modelling The Prevalence Of Down Syndrome With Applications Of Markov Chain Monte Carlo Methods, Isabelle Cella Bray Jan 1998

Modelling The Prevalence Of Down Syndrome With Applications Of Markov Chain Monte Carlo Methods, Isabelle Cella Bray

School of Engineering, Computing and Mathematics Theses

This thesis was motivated by applications in the epidemiology of Down syndrome and prenatal screening for Down syndrome. Methodological problems arising in these applications include under-ascertainment of cases in livebirth studies, double-sampled data with missing observations and coarsening of data. These issues are considered from a classical perspective using maximum likelihood and from a Bayesian viewpoint employing Markov chain Monte Carlo (MCMC) techniques. Livebirth prevalence studies published in the literature used a variety of data collection methods and many are of uncertain completeness. In two of the nine studies an estimate of the level of under-reporting is available. We present …

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Reinforcement Learning In Intelligent Control : A Biologically-Inspired Approach To The Relearning Problem, Brendan D'Cruz Jan 1998

Reinforcement Learning In Intelligent Control : A Biologically-Inspired Approach To The Relearning Problem, Brendan D'Cruz

School of Engineering, Computing and Mathematics Theses

The increasingly complex demands placed on control systems have resulted in a need for intelligent control, an approach that attempts to meet these demands by emulating the capabilities found in biological systems. The need to exploit existing knowledge is a desirable feature of any intelligent control system, and this leads to the relearning problem. The problem arises when a control system is required to effectively learn new knowledge whilst exploiting still useful knowledge from past experiences. This thesis describes the adaptive critic system using reinforcement learning, a computational framework that can effectively address many of the demands in intelligent control, …

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A Young Lens Of Red Sea Water In The Arabian Sea, S. L. Meschanov, G. I. Shapiro Jan 1998

A Young Lens Of Red Sea Water In The Arabian Sea, S. L. Meschanov, G. I. Shapiro

School of Biological and Marine Sciences

No abstract provided.

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Effect Of Dietary Vitamin E And Lipids On Some Immune Parameters Of Turbot (Scophthalmus Maximus L.), Mireille Crampe Jan 1998

Effect Of Dietary Vitamin E And Lipids On Some Immune Parameters Of Turbot (Scophthalmus Maximus L.), Mireille Crampe

School of Biological and Marine Sciences Theses

The effect of dietary vitamin E and dietary lipids on growth and immune parameters of juvenile turbot (Scophthalmus maximus) were investigated in a series of experiments. The aims of the studies were to maximise immune function through dietary modulation to counteract stress induced immunodepression resulting from high stocking densities. In the first experimental trial, the vitamin E requirement for an optimum immune response was studied and revealed that vitamin E depletion induced poor health status, lower growth with some mortalities occurring at the end of the trial. However, supplementation of the diets with high levels of α-tocopherol although ensuring better …

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Measurement Of Suspended Sediment Transport Processes Off The Holderness Coast - Southern North Sea, England, Joanna Catherine Blewett Jan 1998

Measurement Of Suspended Sediment Transport Processes Off The Holderness Coast - Southern North Sea, England, Joanna Catherine Blewett

School of Biological and Marine Sciences Theses

A field campaign was set up as part of the LOIS-RACS coastal program (1994-1996), to identify the near-bed physical processes responsible for suspended sediment movement in shallow water (10-20m depth) off the Holdemess coast, NE England. A new benthic tripod system Boundary Layer Intelligent Sensor System (BLISS) has been developed and deployed along a transect at three sites, normal to the coastline at Tunstall. Measurements of current velocity, suspended sediment concentration (SSC), pressure and CTD were recorded at 5 Hz for 17 minutes every hour, on the same data acquisition system. Results are presented for the summer, July 1995 and …

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Instigating Change In A Globalised Social Environment : The Impact Of Globalisation Upon The Promotion Of Vegetarianism In The United Kingdom, Andrew David Smart Jan 1998

Instigating Change In A Globalised Social Environment : The Impact Of Globalisation Upon The Promotion Of Vegetarianism In The United Kingdom, Andrew David Smart

School of Law, Humanities and Social Sciences Theses

In this thesis I examine globalisation as an ongoing social change to understand how it is routinely reproduced by social actors. To do this I consider the impacts of globalisation in an existing social setting and use a conceptual framework from the sociological literature to interpret and explain the evidence. The empirical materials were gathered during an ethnographic case study of The Vegetarian Society - an interest group that actively promoted social change by presenting everyday individual food consumption in the manner of reflexive 'life politics'. I use the concepts of 'interpenetration', 'relativisation', 'detraditionalisation' and 'institutional reflexivity' to indicate that …

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Patriarchy And Discordant Discourses In The Contemporary Roman Catholic Church : The Voices Of Priests And Women In Parish Settings, Geraldine Sharp Jan 1998

Patriarchy And Discordant Discourses In The Contemporary Roman Catholic Church : The Voices Of Priests And Women In Parish Settings, Geraldine Sharp

School of Law, Humanities and Social Sciences Theses

This thesis explores the sexual theology and contemporary teachings of the Roman Catholic Church and considers their implications for women and priests. It examines the salience and relevance of traditional teaching in the everyday lives of priests and women. It questions the link between a traditionally formed priesthood and the customary beliefs and practices of 'ordinary' English Catholics. Feminist scholarship has produced powerful insights into the ways in which organised religion has subordinated women through patriarchal structures and organisation, although there has been little exploration of the gendered nature of Catholic sexual theology. This thesis suggests that the negative construction …

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A Geometric Approach To Modelling Interacting Populations, Jennifer M. Sharp Jan 1997

A Geometric Approach To Modelling Interacting Populations, Jennifer M. Sharp

School of Engineering, Computing and Mathematics Theses

The purpose of this thesis is to present a different approach to the formulation of differential equation mathematical models for interacting populations. It does this through considering a geometric method. The solution to the differential equations are forced, through theuformulation, to lie on the surface of well known three-dimensional shapes. It is this that allows detailed analysis of how, and why, the solution of the equations behave as they do. The thesis firstly reviews some of the skills and techniques used in the formulation and alysis of differential equation models to give a background for some of the analysis used …

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A Novel Biosensor Using Nanolithographically-Produced Submicron Optical Sources For The Study Of Cell Adhesion And Chemotaxis, Alastair Sheridan Hood Jan 1997

A Novel Biosensor Using Nanolithographically-Produced Submicron Optical Sources For The Study Of Cell Adhesion And Chemotaxis, Alastair Sheridan Hood

School of Engineering, Computing and Mathematics Theses

Cell adhesion and chemotaxis are two key factors determining cell behaviour and differentiation which are currently analysed by microscopic examination of the cell or membrane-associated fluorescence labels. These analyses are often slow, labour intensive and of limited informational content. This thesis describes the physical theory and experimental aspects of an optical method suitable for monitoring cell contact, adhesion to a surface and chemotaxis beyond the conventional limit of optical microscopy by means of a device that utilises both a plain bare surface and arrays of apertures nanolithographically-produced in the surface of a Surface Plasmon Resonance (SPR) sensor structure. Any minute …

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Feedforward Artificial Neural Network Design Utilising Subthreshold Mode Cmos Devices, Dominique Xavier Henri Leon Coue Jan 1997

Feedforward Artificial Neural Network Design Utilising Subthreshold Mode Cmos Devices, Dominique Xavier Henri Leon Coue

School of Engineering, Computing and Mathematics Theses

This thesis reviews various previously reported techniques for simulating artificial neural networks and investigates the design of fully-connected feedforward networks based on MOS transistors operating in the subthreshold mode of conduction as they are suitable for performing compact, low power, implantable pattern recognition systems. The principal objective is to demonstrate that the transfer characteristic of the devices can be fully exploited to design basic processing modules which overcome the linearity range, weight resolution, processing speed, noise and mismatch of components problems associated with weak inversion conduction, and so be used to implement networks which can be trained to perform practical …

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The Innervation And Physiology Of The Cardiac Tissue In Squid, Maria Pernilla Odblom Jan 1997

The Innervation And Physiology Of The Cardiac Tissue In Squid, Maria Pernilla Odblom

School of Biological and Marine Sciences Theses

Cephalopods have one of the most sophisticated cardiovascular systems among the invertebrates; they have an enclosed high pressure blood system, characterised by a double circulation, with one main systemic heart and two gill hearts. The cephalopod cardiac tissues are basically myogenic, but there is evidence for both nervous and hormonal regulation of most parts of the cardiovascular system, although the details of the control systems remain unknown. This study investigated the physiology and innervation of the cardiac tissues of the squid Alloteuthis subulata, Loligo forbesii and L vulgaris. Histological staining techniques established that the cardiac organs in squid are innervated …

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Oxygen-Dependent Metabolism Of Organic Xenobiotics In Marine Fish And Mussel, Laurence David Peters Jan 1997

Oxygen-Dependent Metabolism Of Organic Xenobiotics In Marine Fish And Mussel, Laurence David Peters

School of Biological and Marine Sciences Theses

Studies were undertaken to examine the processes of oxygen-dependent organic xenobiotic metabolism in fish and mussel. The antioxidant enzymes superoxide dismutase (EC 1.15.1.1 ), catalase (EC 1.11.1.6), selenium-dependent glutathione peroxidase (SeGPX; EC 1.11.1.9) glutathione reducate (EC 1.6.4.2), DT Diaphorase (quinone oxidoreductase; EC 1.6.99.2), total GPX activity (sum of SeGPX and Se-independent GPX activities) and levels of cytochrome P450 (CYP) were determined in 13 500g supernatants of embryos, 3- day and 11-day post-hatch larvae of turbot Scophthalmus maximus. The early life stages of S. maximus demonstrated the potential to detoxify reactive oxygen species (ROS), organic peroxides and redox cycling compounds. The …

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The Development Of Novel Techniques For Characterisation Of Marine Zooplankton Over Very Large Spatial Scales, Christopher Paul Gallienne Jan 1997

The Development Of Novel Techniques For Characterisation Of Marine Zooplankton Over Very Large Spatial Scales, Christopher Paul Gallienne

School of Biological and Marine Sciences Theses

Marine zooplankton play an important role in the transfer of CO2 from the atmosphere/ocean system to deeper waters and the sediments. They also provide food for much of the world's fish stocks and in some areas of the ocean depleted of nutrients they sustain phytoplankton growth by recycling nutrients. They therefore have a profound effect on the carbon cycle and upon life in the oceans. There is a perceived lack of information about global distributions of zooplankton needed to validate ecosystems dynamics models, and the traditional methods of survey are inadequate to provide this information. There is a need to …

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Inductive Reasoning In Persecutory Delusional Thought, Ian Walter Shelley Baker Jan 1997

Inductive Reasoning In Persecutory Delusional Thought, Ian Walter Shelley Baker

School of Psychology Theses

Delusions are considered to be one of the primary symptoms of psychosis but until recently have received little empirical investigation. One approach has been to examine the extent to which deluded individuals demonstrate cognitive biases which are different from those of normal controls in inductive reasoning tasks. In this study two hypothesis testing tasks were used to investigate cognitive biases in a group of people with persecutory delusions compared to a group whose delusions had remitted and a normal control group. Participants completed two tasks consisting of a series of visual discrimination problems in which they had to choose between …

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Reflections On Voices, Lynn Mcclelland Jan 1997

Reflections On Voices, Lynn Mcclelland

School of Psychology Theses

Voice hearing (auditory hallucinations) is associated with multiple problems : disturbed behaviour, anxiety, depression, social stigma, and suicide ( Siris 1991 , Barnes et al. 1989, Caldwell & Gottesman 1990). Traditionally voices are seen as a symptom of schizophrenia , psychosis, and mental illness, even though recent estimates of prevalence are 2-4% of the population (Siris 1990, Tien et al. 1993). This view has been challenged by research that has shown that there are many different experiences of voices, positive and negative, and that they are not confined to particular diagnoses or clinical populations (Romme & Escher 1989, Bentall 1990). …

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Intrusive Memories, Coping And Outcome In Depression: Towards A Traumatic Processing Model?, Julie Diane Parker Jan 1997

Intrusive Memories, Coping And Outcome In Depression: Towards A Traumatic Processing Model?, Julie Diane Parker

School of Psychology Theses

Recent studies (e.g. Kuyken & Brewin, 1994a) have noted the presence of high levels of disturbing intrusive memories in depressed women. Intrusive memories are best known as a post-traumatic symptom and have received considerable attention from researchers in this field. The presence of a post-traumatic symptom in depression indicates that trauma models might be useful in refining our understanding and treatment of depression. Predictions based on theories of post-traumatic processing were tested in relation to the intrusive memories of a sample of 26 depressed women. The women showed a pattern of intrusive memory experiences which indicate that their memories are …

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The Potentiation Of Actions By Visual Objects, Michael Richard Edwin Tucker Jan 1997

The Potentiation Of Actions By Visual Objects, Michael Richard Edwin Tucker

School of Psychology Theses

This thesis examines the relation between visual objects and the actions they afford. It is proposed that viewing an object results in the potentiation of the actions that can be made towards it. The proposal is consistent with neurophysiological evidence that suggests that no clear divide exists between visual and motor representation in the dorsal visual pathway, a processing stream that neuropsychological evidence strongly implicates in the visual control of actions. The experimental work presented examines motor system involvement in visual representation when no intention to perform a particular action is present. It is argued that the representation of action-relevant …

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The Development Of On-Line Microwave Digestion Techniques For Environmental Matrices, Kathryn Judith Lamble Jan 1997

The Development Of On-Line Microwave Digestion Techniques For Environmental Matrices, Kathryn Judith Lamble

School of Geography, Earth and Environmental Sciences Theses

As a consequence of our advancing knowledge of the impact of trace elements in environmental and biological systems there is increasing need for quantitative analytical techniques to accurately, sensitively and rapidly determine a wide range of trace elements in environmental samples. Since their emergence in 1975 microwave digestion techniques have revolutionised conventional approaches to sample digestion and have rapidly gained widespread acceptance as an effective method of sample preparation. This thesis describes how a number of novel on-line microwave digestion techniques have been developed, characterised and applied to the digestion of a range of environmental matrices which have proved time …

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Geochemical And Palynological Signals For Palaeoenvironmental Change In South West England, Steven West Jan 1997

Geochemical And Palynological Signals For Palaeoenvironmental Change In South West England, Steven West

School of Geography, Earth and Environmental Sciences Theses

This thesis evaluates the utility of a geochemical technique for the investigation of palaeoenvironmental change in south west England. The method, EDMA (Energy Dispersive X-ray Micro Analysis), is a rapid, non-destructive analysis tool, capable of detecting a large range of geochemical elements. This research examines the most appropriate method of sample preparation for organic soils and peats, and investigates the reliability of results gained from EDMA with respect to conventional bulk geochemical techniques. A detailed study focused on a range of different sedimentary sites in south west England where a variety of palaeoenvironmental changes were thought to occur. Pollen analysis …

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