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An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill Dec 1998

An Improved Method For The Large-Scale Processing Of Woad (Isatis Tinctoria) For Possible Commercial Production Of Woad Indigo, Kg Stoker, Dt Cooke, Dj Hill

Peninsula Medical School

The increasing use of alternative crops has meant the introduction of new technologies to process their products. In this work, an alternative method is presented for the extraction of natural indigo from woad (Isatis tinctoria) based on a technique used to extract indigo from Indigofera spp. This method does not rely on the old fermentation procedure used throughout Northern Europe and is cheap, clean and efficient. Evolved from laboratory-based tests, it involves steeping the leaves at low pH in warm water and extracting the indigo at a higher pH, followed by ultra-filtration of the product, which is then left to …

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Conservation Issues Relating To Maerl Beds As Habitats For Molluscs, Jm Hall-Spencer Jun 1998

Conservation Issues Relating To Maerl Beds As Habitats For Molluscs, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman Jun 1998

Energy Demand Perspectives In Bangladesh, (1992/93 – 2019/20), S Rahman

School of Geography, Earth and Environmental Sciences

The present paper attempted to forecast the demand for primary energy broadly categorized into: (a) commercial (coal, petroleum, natural gas, and hydropower), and (b) non-commercial energy (rice hull and straw, jute stick, firewoods, crop wastes, etc.) for the period 1992/93-2019/20 AD to facilitate in the energy sector planning and development. The demand forecast, based on past time series data (1972/73-1991/92), is made by utilizing two methods: (a) "Market Penetration Theory" that uses trend extrapolation and inter-fuel substitution priniciples, and (b) "Trend Extrapolation Model" taking into account the the exogenous variables, e.g., GDP and energy/GDP ratio. Results reveal that the fractional …

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Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray Jan 1998

Technological Change And Women’S Participation In Crop Production In Bangladesh, S Rahman, Jk Routray

School of Geography, Earth and Environmental Sciences

There is a dearth of information on the employment effects of modern agricultural tech nology on rural women in Bangladesh. The present study1 looks at women's participation in crop production activities, examines their influence in the diffusion of modern technol ogy and their participation in the hired labor market. Data for this study comes from two intensive surveys conducted in the crop years 1989 and 1996 in three agro-ecological regions of Bangladesh. Findings suggest that the prevailing claim-that women are involved only in post- harvest processing of crops-underestimates their contribution to agricultural production. Women's share of total labor is 10-18 …

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Problem Based Learning And Its Use On The Automotive Engineering Design Course At Coventry University, Aj Robotham Jan 1998

Problem Based Learning And Its Use On The Automotive Engineering Design Course At Coventry University, Aj Robotham

School of Engineering, Computing and Mathematics

The Automotive Engineering Design course at Coventry University has been in operation since October 1989 and has earned a reputation for creating able engineers well prepared for industry. When originally conceived, a problem led approach to learning was adopted across the course. This approach best enables the course objectives to be satisfied. However, there is nothing new about problem-based learning for engineering design educators but for our engineering science colleagues a degree of novelty has been encountered by this approach. But is the success of the course purely down to this teaching and learning approach? This paper will discuss the …

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Creating Practitioners Of Design For Quality Through Education, Aj Robotham Jan 1998

Creating Practitioners Of Design For Quality Through Education, Aj Robotham

School of Engineering, Computing and Mathematics

The WDK Workshop in Pedagogics in Design Education provides an ideal opportunity to reflect upon my experiences of teaching engineering design at tertiary level and review some of the fundamental elements of design education practice. In particular, I will reflect upon the design experience provided at Coventry University where I taught until quite recently.

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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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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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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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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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The Generation Of Compound Nominals To Represent The Essence Of Text The Commix System, Jennifer Vivien Norris Jan 1998

The Generation Of Compound Nominals To Represent The Essence Of Text The Commix System, Jennifer Vivien Norris

Other Faculty of Science and Engineering Theses

This thesis concerns the COMMIX system, which automatically extracts information on what a text is about, and generates that information in the highly compacted form of compound nominal expressions. The expressions generated are complex and may include novel terms which do not appear themselves in the input text. From the practical point of view, the work is driven by the need for better representations of content: for representations which are shorter and more concise than would appear in an abstract, yet more informative and representative of the actual aboutness than commonly occurs in indexing expressions and key terms. This additional …

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The Later Political Career Of R.A. Butler 1951-1964, Nicholas Adam Patch Jan 1998

The Later Political Career Of R.A. Butler 1951-1964, Nicholas Adam Patch

Other Faculty of Arts, Humanities and Business Theses

R. A. Butler was one of the most influential and yet enigmatic of twentieth century politicians. He did more than anyone to stimulate the revival of post-war Conservatism, which led to three consecutive general election victories. He was a powerful figure in all Conservative Cabinets from 1951 to 1964, serving in each of the three main offices of state, and he nearly became Prime Minister twice. This thesis seeks to challenge the commonly held belief that the post-war Conservative policies developed by Butler represented an acceptance of the mixed-economy welfare-state, as established by the Labour Government between 1945 and 1951. …

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Automated Interpretation Of The Background Eeg Using Fuzzy Logic, Edward Peter Riddington Jan 1998

Automated Interpretation Of The Background Eeg Using Fuzzy Logic, Edward Peter Riddington

School of Engineering, Computing and Mathematics Theses

A new framework is described for managing uncertainty and for deahng with artefact corruption to introduce objectivity in the interpretation of the electroencephalogram (EEG). Conventionally, EEG interpretation is time consuming and subjective, and is known to show significant inter- and intra-personnel variation. A need thus exists to automate the interpretation of the EEG to provide a more consistent and efficient assessment. However, automated analysis of EEGs by computers is complicated by two major factors. The difficulty of adequately capturing in machine form, the skills and subjective expertise of the experienced electroencephalbgrapher, and the lack of a reliable means of dealing …

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Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen Jan 1998

Automated Diesel Engine Condition & Performance Monitoring & The Application Of Neural Networks To Fault Diagnosis, Christopher Lloyd Owen

School of Engineering, Computing and Mathematics Theses

The overall aim of this research was to design, configure and validate a system which was capable of on-line performance monitoring and fault diagnosis of a diesel engine. This thesis details the development and evaluation of a comprehensive engine test facility and automated engine performance monitoring package. Results of a diesel engine fault study were used to ascertain commonly occurring faults and their realistic severities are discussed. The research shows how computer simulation and rig testing can be applied to validate the effects of faults on engine performance and quantify fault severities. A substantial amount of engine test work has …

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Intelligent Pattern Analysis Of The Foetal Electrocardiogram, Nicholas John Outram Jan 1998

Intelligent Pattern Analysis Of The Foetal Electrocardiogram, Nicholas John Outram

School of Engineering, Computing and Mathematics Theses

The aim of the project on which this thesis is based is to develop reliable techniques for foetal electrocardiogram (ECG) based monitoring, to reduce incidents of unnecessary medical intervention and foetal injury during labour. World-wide electronic foetal monitoring is based almost entirely on the cardiotocogram (CTG), which is a continuous display of the foetal heart rate (FHR) pattern together with the contraction of the womb. Despite the widespread use of the CTG, there is no significant improvement in foetal outcome. In the UK alone it is estimated that birth related negligence claims cost the health authorities over £400M per-annum. An …

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3d Object Recognition Based On Constrained 2d Views, Levente Toth Jan 1998

3d Object Recognition Based On Constrained 2d Views, Levente Toth

School of Engineering, Computing and Mathematics Theses

The aim of the present work was to build a novel 3D object recognition system capable of classifying man-made and natural objects based on single 2D views. The approach to this problem has been one motivated by recent theories on biological vision and multiresolution analysis. The project's objectives were the implementation of a system that is able to deal with simple 3D scenes and constitutes an engineering solution to the problem of 3D object recognition, allowing the proposed recognition system to operate in a practically acceptable time frame. The developed system takes further the work on automatic classification of marine …

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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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The Balance Between Activation And Inhibition In Stereotype Use, Na Wyer, Dl Hamilton Jan 1998

The Balance Between Activation And Inhibition In Stereotype Use, Na Wyer, Dl Hamilton

School of Psychology

No abstract provided.

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Investigation Into The Materials And Manufacturing Of A New Thin Film Magnetoresistive Sensor, Yong Qing Ma Jan 1998

Investigation Into The Materials And Manufacturing Of A New Thin Film Magnetoresistive Sensor, Yong Qing Ma

School of Engineering, Computing and Mathematics Theses

There is increasing interest in utilising very thin anisotropic magnetoresistive films (typically in the range of a few nano-metres) to make magnetic sensors which can be made very small and with a high signal-to-noise ratio. In this thesis, a new type of sensor is investigated which has a pair of thin film MR stripes whose magnetisation is switched alternately in opposite directions using bias fields from currents in overlay conductor films. The investigation considers in particular the Barkhausen noise in these sensors and its relationship with factors such as sensor film thickness. The effect of thickness and grain size on …

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Investigation Into Submicron Track Positioning And Following Technology For Computer Magnetic Disks, Baolin Tan Jan 1998

Investigation Into Submicron Track Positioning And Following Technology For Computer Magnetic Disks, Baolin Tan

School of Engineering, Computing and Mathematics Theses

In the recent past some magnetic heads with submicron trackwidth have been developed in order to increase track density of computer magnetic disks, however a servo control system for a submicron trackwidth head has not been investigated. The main objectives of this work are to investigate and develop a new servo pattern recording model, a new position sensor, actuator, servo controller used for submicron track positioning and following on a computer hard disk with ultrahigh track density, to increase its capacity. In this position sensor study, new modes of reading and writing servo information for longitudinal and perpendicular magnetic recording …

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The Modes Of Action Of Toxicants On The Cardiac Physiology Of The Blue Mussel, Mytilus Edulis, And The Common Shore Crab, Carcinus Maenas, Timothy Mark Curtis Jan 1998

The Modes Of Action Of Toxicants On The Cardiac Physiology Of The Blue Mussel, Mytilus Edulis, And The Common Shore Crab, Carcinus Maenas, Timothy Mark Curtis

School of Biological and Marine Sciences Theses

The primary aim of this thesis was to establish the mode of action of the heavy metal, copper, on the cardiac physiology of the blue mussel, Mytilus edulis. Exposure of specimens of M.edulis to dissolved copper led to a decrease in heart rate and an increase in heart rate variability (HRV). The concentration of copper causing a 50% reduction in heart rate was found to be 0.8µM, while the concentration causing a 50% increase in HRV was 0.06µM (48 h EC50s). Simultaneous measurements of valve activity indicated that the observed bradycardia was not caused by valve closure. Subsequently, it was …

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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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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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Stability And Compatibility Of Four Cytotoxic Drug Infusions In The Graseby 9000 Ambulatory Pump, Gj Sewell, Mj Priston Jan 1998

Stability And Compatibility Of Four Cytotoxic Drug Infusions In The Graseby 9000 Ambulatory Pump, Gj Sewell, Mj Priston

School of Health Professions

Objective. The purpose of this study was to determine the stability of three cytotoxic infusions in the Graseby 9000 ambulatory pump (Graseby Medical, Watford, UK) under both refrigerated storage and in-use conditions. The infusions studied were: (a) doxorubicin (2 mg/mL) plus vincristine (0.2 mg/mL) and (b) ifosfamide (20 mg/mL) plus mesna (20 mg/mL) and etoposide (0.5 mg/mL). In each case, the diluent was water for injection. Methods. Graseby 9000 medication cassettes, each containing one of three infusions studied, were incubated at either 8°C or 37°C to represent refrigerated storage or 'in-use' temperatures, respectively. Samples were withdrawn for chemical and physical …

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Protein Phosphatase Β, A Putative Type‐2a Protein Phosphatase From The Human Malaria Parasite Plasmodium Falciparum, J Li, Da Baker Oct 1997

Protein Phosphatase Β, A Putative Type‐2a Protein Phosphatase From The Human Malaria Parasite Plasmodium Falciparum, J Li, Da Baker

Peninsula Medical School

Protein phosphatases play a critical role in the regulation of the eukaryotic cell cycle and signal transduction. A putative protein serine/threonine phosphatase gene has been isolated from the human malaria parasite Plasmodium falciparum. The gene has an unusual intron that contains four repeats of 32 nucleotides and displays a high degree of size polymorphism among different strains of P. falciparum. The open reading frame reconstituted by removal of the intron encodes a protein of 466 amino acids with a predicted molecular mass of approximately 53.7 kDa. The encoded protein, termed protein phosphatase β (PP-β), is composed of two distinct domains. …

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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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Capture And Release Of Lagrangian Floats By Eddies In Shear Flow, G. I. Shapiro, E. D. Barton, S. L. Meschanov Jan 1997

Capture And Release Of Lagrangian Floats By Eddies In Shear Flow, G. I. Shapiro, E. D. Barton, S. L. Meschanov

School of Biological and Marine Sciences

No abstract provided.

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System Identification Theory Approach To Cohesive Sediment Transport Modelling, Huixin Chen Jan 1997

System Identification Theory Approach To Cohesive Sediment Transport Modelling, Huixin Chen

School of Engineering, Computing and Mathematics Theses

Two aspects of the modelling sediment transport are investigated. One is the univariate time series modelling the current velocity dynamics. The other is the multivariate time series modelling the suspended sediment concentration dynamics. Cohesive sediment dynamics and numerical sediment transport model are reviewed and investigated. The system identification theory and time series analysis method are developed and applied to set up the time series model for current velocity and suspended sediment dynamics. In this thesis, the cohesive sediment dynamics is considered as an unknown stochastic system to be identified. The study includes the model structure determination, system order estimation and …

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Reversal Of Parkinsonian Symptoms In Primates By Antagonism Of Excitatory Amino Acid Transmission: Potential Mechanisms Of Action., I. J. Mitchell, C. B. Carroll Jan 1997

Reversal Of Parkinsonian Symptoms In Primates By Antagonism Of Excitatory Amino Acid Transmission: Potential Mechanisms Of Action., I. J. Mitchell, C. B. Carroll

Peninsula Medical School

Parkinsonism is characterised by overactive glutamatergic transmission in the cortico-striatal and subthalamo-medial pallidal pathways. Local blockade of glutamatergic transmission in these pathways can alleviate parkinsonian symptoms. The effectiveness of the treatment, however, is often limited by the simultaneous appearance of unwanted side-effects. These side-effects, including ataxia and dissociative anaesthesia, are particularly problematic when N-methyl-D-aspartate (NMDA) antagonists are used. In an attempt to overcome these problems we have attempted to manipulate excitatory amino acid (EAA)-mediated neurotransmission indirectly by targeting the NMDA receptor associated modulatory sites. We review evidence which demonstrates that antagonists for both the NMDA associated glycine and polyamine sites …

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Privatisation, Rural Railways And Community Development, Theresa Maria Lowndes Jan 1997

Privatisation, Rural Railways And Community Development, Theresa Maria Lowndes

School of Geography, Earth and Environmental Sciences Theses

This thesis examines two separate, but interrelated, issues, namely rail privatisation and rural dependency on the availability of rail transport. The thesis was based on the proposition that rural accessibility permits the development and sustainability of the social and economic lives of a community and that this interrelationship is currently threatened by rail privatisation and the associated risks of line closures or service cutbacks. To test this proposition a thorough investigation into the theory and practice of privatisation was completed, together with a comprehensive survey of the travel arrangements of people living in rural communities served by branch line railways. …

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