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Cell Division And Migration In A `Genotype' For Neural Networks, A Cangelosi, D Parisi, S Nolfi Nov 1994

Cell Division And Migration In A `Genotype' For Neural Networks, A Cangelosi, D Parisi, S Nolfi

School of Engineering, Computing and Mathematics

Much research has recently been dedicated to applying genetic algorithms to populations of neural networks. However. While in real organisms the inherited genotype maps in complex ways into the resulting phenotype, in most of this research the development process that creates the individual phenotype is ignored. In this paper we present a model of neural development which includes cell division and cell migration in addition to axonal growth and branching. This reflects, in a very simplified way, what happens in the ontogeny of real organisms. The development process of our artificial organisms shows successive phases of functional differentiation and specialization. …

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Temperature And Period Dependence In The Post-Diapause Development Of The Cabbage Root Fly, Delia Radicum, Lorne George Roberts Jan 1994

Temperature And Period Dependence In The Post-Diapause Development Of The Cabbage Root Fly, Delia Radicum, Lorne George Roberts

School of Biological and Marine Sciences Theses

The cabbage root fly (Delia radicum (L.) (Diptera: Anthomyiidae) (Pont, 1981)), as it is known in the U.K. (Anon.,1947), or the cabbage maggot, as it is known in North America and Canada (Muesebeck, 1942) has been described by a number of different generic names and specific epithets. First described by Bouche in 1833 as Anthomyia brassicae, it is also known as Hylemyia, Erioischia, Chonophila, Phorbia and Delia brassicae. However, it is known now as Delia radicum (L.). D. radicum is found to cause serious damage to brassica crops in the Holarctic region (35-60°N) (Shoene, 1916; de Wilde, 1947). It is …

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The Influence Of Larval Density On Larval Growth, And The Consequences For Adult Survival And Reproductive Success In The Damselfly Calopteryx Virgo (Odonata), Claire Louise Lambert Jan 1994

The Influence Of Larval Density On Larval Growth, And The Consequences For Adult Survival And Reproductive Success In The Damselfly Calopteryx Virgo (Odonata), Claire Louise Lambert

School of Biological and Marine Sciences Theses

This study of a population of C.virgo at Burrator, Dartmoor looks for signs of a population regulation mechanism acting through the effects of larval density on larval growth. The consequences of adult body size and emergence time for survival and reproductive success are also examined to look for further regulation mechanisms, and opportunities for natural and sexual selection; in particular the importance of body size to territorial males. Although there were significant differences in patterns of growth and body size within and between year classes of larvae, the differences were were not related to density. Smaller, later developing larvae were …

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The Water-Soluble Vitamin Nutrition Of The Gilthead Seabream (Sparus Aurata L.), Paul Christopher Morris Jan 1994

The Water-Soluble Vitamin Nutrition Of The Gilthead Seabream (Sparus Aurata L.), Paul Christopher Morris

School of Biological and Marine Sciences Theses

Given the paucity of information with regards the micronutrient requirements of the currently expanding number of cultured marine species, a series of investigations was undertaken to examine the water-soluble vitamin nutrition of the gilthead seabream (Sparus aurata L.). A preliminary study identified the qualitative requirement of this species for ascorbic acid, the B complex vitamins and choline for the maintenance of health and optimum productivity. Based on the observations of the preliminary experiment, a study was designed which allowed the development of a semi-purified diet and illustrated the qualitative requirement of the gilthead seabream for thiamin, niacin, riboflavin, pyridoxine and …

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Development And Testing Of An Instrument To Measure Estuarine Floc Size And Settling Velocity In Situ, Michael Jim Fennessy Jan 1994

Development And Testing Of An Instrument To Measure Estuarine Floc Size And Settling Velocity In Situ, Michael Jim Fennessy

School of Biological and Marine Sciences Theses

An instrument has been developed to observe the settling of individual flocs in turbid water in order to to measure size and settling velocity spectra of estuarine cohesive suspended sediments. INSSEV - IN Situ SEttling Velocity instrument - is bed mounted and comprises a computer controlled decelerator chamber that collects a sample of water from which some of the suspended matter is allowed to enter the top of a settling column. The settling flocs are viewed using a miniature video system. Subsequent analysis of video tapes provides direct measurements of size and settling velocity of individual flocs down to 20 …

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Gastrointestinal Antigen Processing And Its Relevance To Enteric Vaccine Delivery In Rainbow Trout, Oncorhynchus Mykiss (Walbaum, 1792), Edward Charles Lavelle Jan 1994

Gastrointestinal Antigen Processing And Its Relevance To Enteric Vaccine Delivery In Rainbow Trout, Oncorhynchus Mykiss (Walbaum, 1792), Edward Charles Lavelle

School of Biological and Marine Sciences Theses

An investigation of antigen processing in the rainbow trout gastrointestine was carried out to provide a rational basis for the design of oral delivery systems for protein antigens. Using in vitro systems involving isolated lumenal enzymes and gut cell suspensions the degradation of human gamma globulin (HGG) and bovine serum albumin (BSA) was analysed by Western blotting and laser densitometry. Proteolysis by lumenal enzymes was dependant on pH and temperature and serine proteases were found to be partly responsible for antigen degradation in the intestine. The extent of intracellular proteolysis depended on the antigen used and on the gut region …

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Seawater Ph And The Oceanic Carbon Cycle, Richard Garth James Bellerby Jan 1994

Seawater Ph And The Oceanic Carbon Cycle, Richard Garth James Bellerby

School of Biological and Marine Sciences Theses

The buffering of carbon dioxide in seawater and the intimate relationship between the carbonate system, air-sea gas exchange and biological productivity in the oceans is described. Characterisation of the carbonate system is enabled through the concurrent measurement of any two of the variables pH, alkalinity, TCO2 and pCO2. It is identified that to obtain the high density, high precision measurements necessary to better constrain carbon cycle models, with respect to estimating the effect of anthropogenic carbon release to the atmosphere, it will be necessary to develop in situ techniques for the measurement of pH and pCO2. The theory of pH …

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Genotoxicology Of Diesel Engine Exhaust Emissions In Cultured Mammalian Cells, Shaun Thomas Kingston Jan 1994

Genotoxicology Of Diesel Engine Exhaust Emissions In Cultured Mammalian Cells, Shaun Thomas Kingston

School of Biological and Marine Sciences Theses

Diesel exhaust emissions were collected from a 2 litre direct injection diesel engine using the Total Exhaust Solvent Scrubbing Apparatus (TESSA). Emission samples were collected from a series of two minute engine runs, at a variety of engine speeds and loads which covered the full operating range of the engine. The exhaust extracts collected were then tested for their cytotoxicity and mutagenic potential in cultured Chinese hamster cells. Emission samples were found to be extremely toxic, with most causing 100% cytotoxicity at concentrations of less than 100 /µg/ml. Chromosome aberration studies indicated that less than 50% of the emission samples …

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Waves, Currents And Sand Transport Predictors On A Macro-Tidal Beach, Yolanda Lucy Margaret Foote Jan 1994

Waves, Currents And Sand Transport Predictors On A Macro-Tidal Beach, Yolanda Lucy Margaret Foote

School of Biological and Marine Sciences Theses

A field experiment was carried out at Spurn Head, Humberside as part of the British Beach and Nearshore Dynamics (B-BAND) project. The B-BAND measurements at Spurn Head were obtained over 10 tidal cycles during April 1991. Three tidal cycles are described in the present work which encompass a spectrum of conditions from storm to calm. The beach at the field site comprised a veneer of sand and shingle overlying a glacial till shore plug.

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Effect Of Copper On The Gill Structure Of A Euryhaline Crab, Carcinus Maenas (Crustacea: Decapoda), Sarah Louise Lawson Jan 1994

Effect Of Copper On The Gill Structure Of A Euryhaline Crab, Carcinus Maenas (Crustacea: Decapoda), Sarah Louise Lawson

School of Biological and Marine Sciences Theses

A posterior gill of the common shore crab Carcinus maenas (Crustacea:Decapoda) was used to study the effects of sublethal copper concentrations on gill morphometry, and gill cell ultrastructure and distribution. Primarily, the ultrastructure and distribution of gill cells in the untreated gill of crabs acclimated to 35‰ seawater were characterised. Gill ultrastructure was subsequently shown to vary markedly at 10‰ compared to 35‰ seawater. Ultrastructural and distributional, rather than gross morphological, change occurred in the gill following exposure to copper at each salinity. Ultrastructural studies showed that as the length of copper exposure increased the gill epithelial layer became highly …

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Guidelines For The Design Of Enhanced, Cost Effective Networks In A Manufacturing Environment, Benn Michael Lines Jan 1994

Guidelines For The Design Of Enhanced, Cost Effective Networks In A Manufacturing Environment, Benn Michael Lines

School of Engineering, Computing and Mathematics Theses

Investigations into the transmission of real-time interactive speech over local area networks (LAN) in an industriai/commerciai environment to eventually obviate the need for a private automatic branch exchange and ultimately prepare the way for a single interactive integrated information system (PS) that provides work stations, which are networked via a LAN, with a fully interactive speech and graphics facility commensurate with the future requirements in computer integrated manufacturing (CIM). The reasons for conducting this programme of research were that existing LANs do not offer a real time interactive speech facility. Any verbal communication between workstation users on the LAN has …

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The Technique Of Determination Of Structural Parameters From Forced Vibration Testing, Wai Fan Tsang Jan 1994

The Technique Of Determination Of Structural Parameters From Forced Vibration Testing, Wai Fan Tsang

School of Engineering, Computing and Mathematics Theses

This thesis details the results of an investigation into a technique for determination of "useful" structural parameters from forced vibration testing. The implementation of this technique to full scale civil engineering structures was achieved by several developments in the experimental and computational fronts: a vibration generator and a computer-aided-testing system for the former and two computational algorithms for the latter. The experimental developments are instrumental to exciting large structures and acquisition of large quantities of useful data in digital format. These data serve as inputs to the computational algorithms whose outputs are structural parameters. These parameters are in either modal …

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Neural Models Of Subcortical Auditory Processing, Susan Lynda Mccabe Jan 1994

Neural Models Of Subcortical Auditory Processing, Susan Lynda Mccabe

School of Engineering, Computing and Mathematics Theses

An important feature of the auditory system is its ability to distinguish many simultaneous sound sources. The primary goal of this work was to understand how a robust, preattentive analysis of the auditory scene is accomplished by the subcortical auditory system. Reasonably accurate modelling of the morphology and organisation of the relevant auditory nuclei, was seen as being of great importance. The formulation of plausible models and their subsequent simulation was found to be invaluable in elucidating biological processes and in highlighting areas of uncertainty. In the thesis, a review of important aspects of mammalian auditory processing is presented and …

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An Investigation Into The Applicability Of Nmr For Cure Monitoring Of Composites, Angela Lois Newbury Jan 1994

An Investigation Into The Applicability Of Nmr For Cure Monitoring Of Composites, Angela Lois Newbury

School of Engineering, Computing and Mathematics Theses

Fibre-reinforced polymer-matrix composite materials have highly attractive physical properties which justify the present rapid increase in applications within industry. However, composite materials suffer, like every structural material, from a failure to achieve their design properties. Therefore this research project has investigated the processing of resin used in composite materials. Initially the research programme has been concerned with the cure of epoxy resins (specifically Araldite MY750 epoxy resin system), the behaviour of the resin as it cures and how the extent of cure can affect the mechanical properties of components. Therefore, investigations have been carried out into how resin cure can …

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The Effects Of Control, Feedback And Predictability On Psychophysiological Indices Of Stress, Jeremy Goslin Jan 1994

The Effects Of Control, Feedback And Predictability On Psychophysiological Indices Of Stress, Jeremy Goslin

School of Psychology Theses

The primary aim of this thesis was to examine the psychophysiological effects of predictability, personal control and feedback within the biopsychosocial framework of the stress-diathesis model proposed by Steptoe (1991).

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Noise Source Location In The Built Environment, Using A Simple Microphone Array, Michael Latham Jan 1994

Noise Source Location In The Built Environment, Using A Simple Microphone Array, Michael Latham

School of Engineering, Computing and Mathematics Theses

An inadequate level of noise attenuation provided by a building element is frequently the result of a lack of completeness in the construction. This often invisible fault acts as a noise source in a room, so in order to undertake remedial work the source position must be found. Recently, near field noise intensity measurement has been the popular method for noise source location in buildings. This method of using intensity studies requires a grid of readings to be taken. An alternative method, the one used in this work, employs a different strategy. Here, the source location is identified by direction …

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An Investigation Into An Expert System For Telecommunication Network Design, Paul Laurence Reynolds Jan 1994

An Investigation Into An Expert System For Telecommunication Network Design, Paul Laurence Reynolds

School of Engineering, Computing and Mathematics Theses

Many telephone companies, especially in Eastern-Europe and the 'third world', are developing new telephone networks. In such situations the network design engineer needs computer based tools that not only supplement his own knowledge but also help him to cope with situations where not all the information necessary for the design is available. Often traditional network design tools are somewhat removed from the practical world for which they were developed. They often ignore the significant uncertain and statistical nature of the input data. They use data taken from a fixed point in time to solve a time variable problem, and the …

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Analytic Cohomology On Blown - Up Twistor Space, Robin Edward Horan Jan 1994

Analytic Cohomology On Blown - Up Twistor Space, Robin Edward Horan

School of Engineering, Computing and Mathematics Theses

A flat twistor space is a complex 3 - manifold having the property that every point of the manifold has a neighbourhood which is biholomorphic to a neighbourhood of a complex projective line in complex projective 3 - space. The Penrose transform provides an isomorphism between holomorphic structures on twistor spaces and certain field equations on (Riemannian or Lorentzian) space - times. The initial examples studied by Penrose were solutions to zero rest mass equations and, amongst these, the elementary states were of particular interest. These were elements of a sheaf cohomology group having a singularity on a particular complex …

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Teachers' Involvement In Decision-Making: A Case-Study Of A Primary School At A Time Of Rapid Change, Denis Hayes Jan 1994

Teachers' Involvement In Decision-Making: A Case-Study Of A Primary School At A Time Of Rapid Change, Denis Hayes

Plymouth Institute of Education Theses

This thesis rests upon a case-study of staff involvement in decision-making during a time of rapid change in the education system of England and Wales in a Church of England (aided) primary school for children aged 5 to 12. referred to under the pseudonym St. Kerensa's. Against this background of change. I develop a framework for the analysis of teacher involvement with special reference to the influence of statutory demands, focusing particularly upon the headteacher's attempts to establish a climate of collaboration and staff reactions to the opportunities for involvement. The imposition of govemment reforms affects the development of intra-school …

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School Based Training: A Comparative Case Study Of An Articled Teacher Course And A One Year Pgce, Caroline Whiting Jan 1994

School Based Training: A Comparative Case Study Of An Articled Teacher Course And A One Year Pgce, Caroline Whiting

Plymouth Institute of Education Theses

This research is based on a case study of two primary Post Graduate Certificate in Education (PGCE) courses at the same university which was carried out at a time of rapid change and major reform. One of those courses, the Articled Teacher (AT) PGCE was of the 'school based' variety much heralded at the time as the way forward for the preparation of teachers. In this scheme, learner teachers were based, usually alone, for two years in one school in the care of a mentor, with a chance of a 'teaching practice' in another school. The ATs came into the …

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Investigation Of Chelating Dye Impregnated Resins For The Ion Chromatographic Determination Of Trace Metals, Brett Paull Jan 1994

Investigation Of Chelating Dye Impregnated Resins For The Ion Chromatographic Determination Of Trace Metals, Brett Paull

School of Geography, Earth and Environmental Sciences Theses

A high-performance chelation ion chromatography (HPCIC) system using chelating dye impregnated resins for the determination of trace metals in various complex matrices is described. The parameters involved in the production of dye impregnated chelating columns have been identified and optimised, A range of chelating dyes have been impregnated successfully into high-performance substrates, producing a number of chelating columns capable of both metal preconcentration and separations. Each of the chelating columns produced exhibited unique chelating properties. These columns have been classified in terms of metal retention characteristics, separation capability and efficiency, dye loading and column capacities. A number of the above …

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The Determination Of Trace Metals In Sea Water Using Icp-Ms, Martin John Bloxham Jan 1994

The Determination Of Trace Metals In Sea Water Using Icp-Ms, Martin John Bloxham

School of Geography, Earth and Environmental Sciences Theses

Inductively coupled plasma-mass spectrometry (ICP-MS) offers 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 species can be introduced via precursor atoms in atmospheric gases, the sample matrix or impurities in the argon support gas. This thesis describes the development of a portfolio of analytical methods coupled with ICP-MS detection for the determination of trace metals such as manganese, cobalt, copper, nickel, zinc, mercury and lead in complex matrices such as sea water. A literature review of coupled techniques is given in Chapter one. …

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The Dissolution And Photodegradation Of Kuwait Crude Oil In Seawater, Lulwa Nasser Ali Jan 1994

The Dissolution And Photodegradation Of Kuwait Crude Oil In Seawater, Lulwa Nasser Ali

School of Geography, Earth and Environmental Sciences Theses

To further a quantitative understanding of the effects of weathering on oil spilled at sea, a series of laboratory experiments were conducted to investigate the dissolution and photodegradation kinetics of Kuwait crude oil in seawater. A simple and practical method was developed for the preparation of stable homogeneous samples of sea water-soluble oil (SWSF) at 25 "C. The dissolution was monitored by two independent but complementary methods; total dissolved oil was measured by a photochemical dissolved organic carbon (DOC) technique whilst the dominant soluble constituents, aromatic hydrocarbons, were measured by ultraviolet-fluorescence (UVF) spectrophotometry. Maximum dissolution was observed after slowly stirring …

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The Sub-Surface Distribution Of Some Heavy Metals Following Sewage Sludge Injection Into Grassland Soils, Rachel Brown Jan 1994

The Sub-Surface Distribution Of Some Heavy Metals Following Sewage Sludge Injection Into Grassland Soils, Rachel Brown

School of Geography, Earth and Environmental Sciences Theses

The use of suitable sewage sludge in agriculture is currently its cheapest disposal option,, both in terms of monetary cost, resource utilisation and environmental impact Monitoring of die heavy metal content of the soil after sludge application is required by European Council Du-ective 86/278/EEC, and whilst the behaviour of metals from surface-applied sludge is well documented, the behaviour following other methods of application has received litde attention. The most important alternative land application method cturentiy in use is the subsurface injection of sludge. In this project, field- and laboratory-based experiments were set up to describe the postinjection disttibution of Cd, …

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The Characterisation Of Engine Oils By Liquid Chromatography With Luminescence Detection, Simon Wyndham Lewis Jan 1994

The Characterisation Of Engine Oils By Liquid Chromatography With Luminescence Detection, Simon Wyndham Lewis

School of Geography, Earth and Environmental Sciences Theses

This thesis describes the development of pre column derivatisation reactions for the selective determination of organic functional groups in oxidised oils by liquid chromatography (LC) with luminescence detection. The testing of oils for oxidative stability and the current methods of oil analysis are reviewed in chapter one. An overview of LC and luminescence spectrometry, with particular regard to chemiluminescence (CL) is also presented. Chapter two is a flow injection investigation of the experimental variables of the peroxyoxalate CL reaction. Two aryl oxalates; bis(2,4-dinitrophenyl)oxalate and bis(2,4,6-tricblorophenyl)oxalate were compared for their suitability to LC detection. A charge coupled device (CCD) was used …

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Development Of Improved Methods For The Analysis Of Metalloporphyrins In Coals, Sediments And Oils, Warren Gavin Pretorius Jan 1994

Development Of Improved Methods For The Analysis Of Metalloporphyrins In Coals, Sediments And Oils, Warren Gavin Pretorius

School of Geography, Earth and Environmental Sciences Theses

A high temperature gas chromatography (HTGC)-inductively coupled plasma-mass spectrometry (ICP-MS) interface was successfully developed which allowed the analysis of metalloporphyrins (Retention Index >6000), with detection limits of less than 1 nanogram on column. The system was used together with conventional HTGC-flame ionization detection and HTGC-mass spectrometry (MS) for the analysis of geoporphyrin fractions from Julia Creek, Serpiano, Marl Slate and Green River shales. This allowed the rapid fingerprinting of the metals chelated to the porphyrins in these samples. Previously unreported titanium porphyrins were detected in two of these shales, the Marl Slate and Julia Creek. An iron porphyrin fraction from …

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Bracken (Pteridium Aquilinum (L.) Kuhn) Stand Characterisation On The North York Moors: A Study Of The Rhizome And Frond System With Regard To A Large Scale Control Programme, Stephen Mark Holloway Jan 1994

Bracken (Pteridium Aquilinum (L.) Kuhn) Stand Characterisation On The North York Moors: A Study Of The Rhizome And Frond System With Regard To A Large Scale Control Programme, Stephen Mark Holloway

School of Geography, Earth and Environmental Sciences Theses

Large-scale rhizome sampling on the North York Moors together with an assessment of published bracken sampling protocols concluded that small-scale sampling of the rhizome system is inadequate to describe upland bracken stands accurately. It is also concluded that the frond cannot be used as an indicator of the rhizome system before or after treatment to achieve bracken control. An improved sampling strategy is proposed which increases the reliability of data collected and the validity of any conclusions drawn form such data. The structure of bracken rhizome systems, from separate stands on the North York Moors, were found to be distinct …

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An Investigation Of Seismic Attenuation In Marine Sediments, Roderick David Eddies Jan 1994

An Investigation Of Seismic Attenuation In Marine Sediments, Roderick David Eddies

School of Geography, Earth and Environmental Sciences Theses

There have been relatively few investigations into the attenuation properties of unconsolidated sediments using marine surface seismic data. Several methods of measuring attenuation were assessed for reliability in a noise-free case and with the addition of noise using a set of synthetically absorbed and dispersed wavelets. Wavelet modelling proved to be superior to the other techniques, followed by spectrum modelling and the spectral ratios method. Complex trace analysis using the analytical signal proved to be unreliable for non-sinusoidal wavelets, whilst the risetime method was found to be very susceptible to noise for practical purposes. Numerical modelling was carried out to …

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Pore-Level Fluid Migration In Reservoir Sandstones, Adam Keith Moss Jan 1994

Pore-Level Fluid Migration In Reservoir Sandstones, Adam Keith Moss

School of Geography, Earth and Environmental Sciences Theses

The void space properties of a set of gas reservoir sandstone samples have been measured. The properties include porosity, absolute gas permeability, electrical resistivity formation factor and tortuosity. The mineralogy of each sandstone was determined by scanning electron microscopy and energy dispersive x-ray analysis. Mercury intrusion and extrusion data have been measured for most of the sandstone samples. A new procedure for measuring the degree and range of void size correlations within resin-filled sandstones has been developed. Image analysis of backscattered electron micrographs of these samples supplies void size and positional information. A "semi-variogram" study of void size and coordinate …

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Obesity And The Experience Of Eating In Adult, American, Caucasian Women: A Grounded Theory Approach, Sheryl Sue Russell Jan 1994

Obesity And The Experience Of Eating In Adult, American, Caucasian Women: A Grounded Theory Approach, Sheryl Sue Russell

Other Faculty of Health Theses

The search to unravel the complex phenomenon of obesity has been pursued for centuries. Theoretical postulations regarding the etiology of obesity and subsequent management strategies are numerous and complex. Despite decades of clinical application, the rising prevalence of obesity remains essentially unchanged. Clearly it is time to consider a new perspective. In view of the continued failure of programs to effectively achieve successful long-term weight management, a re-evaluation of the phenomenon of eating is warranted. A grounded theory design provided the opportunity to explore this phenomenon in a new light. This study attempts to understand the phenomenon of eating in …

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