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Catchment Scale Monitoring And Modelling Of Phosphorus Using Flow Injection Analysis And An Export Coefficient Model, Grady Scott Hanrahan Jan 2001

Catchment Scale Monitoring And Modelling Of Phosphorus Using Flow Injection Analysis And An Export Coefficient Model, Grady Scott Hanrahan

School of Geography, Earth and Environmental Sciences Theses

Acquiring high quality in situ analytical data with good temporal resolution is required for developing models of phosphorus transport and biogeochemical behaviour. Chapter One describes the behaviour of phosphorus in the aquatic environment, its sources, its role in the eutrophication process and legislation to control its release into aquatic systems. It also summarises analytical techniques for the determination of phosphorus in natural waters. An examination of the hypothesis that the export coefficient modelling approach can be used to predict phosphorus loading in the River Frome catchment, Dorset on an armual and seasonal (monthly) basis is presented in Chapter Two. The …

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The Development Of A Holistic Expert System For Integrated Coastal Zone Management, Antoni Bruce Moore Jan 2001

The Development Of A Holistic Expert System For Integrated Coastal Zone Management, Antoni Bruce Moore

School of Geography, Earth and Environmental Sciences Theses

Coastal data and information comprise a massive and complex resource, which is vital to the practice of Integrated Coastal Zone Management (ICZM), an increasingly important application. ICZM is just as complex, but uses the holistic paradigm to deal with the sophistication. The application domain and its resource require a tool of matching characteristics, which is facilitated by the current wide availability of high performance computing. An object-oriented expert system, COAMES, has been constructed to prove this concept. The application of expert systems to ICZM in particular has been flagged as a viable challenge and yet very few have taken it …

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An Evaluation Of The Environmental Fate Of Reactive Dyes, Malcolm John Hetheridge Jan 2001

An Evaluation Of The Environmental Fate Of Reactive Dyes, Malcolm John Hetheridge

School of Geography, Earth and Environmental Sciences Theses

Dyestuffs are widely used industrial chemicals, yet surprisingly little is known about their fate in the environment. The potential modes of transformation and removal of reactive dyes in treatment and in the environment are principally through anaerobic and aerobic biodegradation and photodegradation. The research herein describes the use of LC-MS analysis with laboratory simulations to develop a better understanding of the occurrence and fate of reactive dyes and their degradation products in the aquatic environment. One reason for the lack of information on the environmental fate of reactive dyes has been the paucity of robust analytical methods suitable for the …

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The Biogeochemical Cycling Of Dissolved Organic Carbon In The Iberian Margin Upwelling System (Ne Atlantic Ocean, Geogina Spyres Jan 2001

The Biogeochemical Cycling Of Dissolved Organic Carbon In The Iberian Margin Upwelling System (Ne Atlantic Ocean, Geogina Spyres

School of Geography, Earth and Environmental Sciences Theses

Dissolved organic carbon (DOC) is the quantitatively most important organic carbon reservoir in the world's oceans and its determination at ocean margins, where the exchange of terrestrial and oceanic organic matter occurs, is important for estimating cross-slope fluxes to deep waters. With the increased accuracy and precision (-1%) of analytical methodologies, small changes in the DOC pool can be detected (i.e. 1- 2uM-C). This study investigated the biogeochemical cycling of DOC at the Iberian Margin upwelling system (42-43°N, --9-10°W), where contrasting seasonal hydrologic phenomena occur (e.g. summer upwelling, winter poleward current). Spatial and temporal DOC distributions were determined using high …

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Treatment Of Musculoskeletal Pain With The Sting Of The Stinging Nettle: Urtica Dioica, Colin F Randall Jan 2001

Treatment Of Musculoskeletal Pain With The Sting Of The Stinging Nettle: Urtica Dioica, Colin F Randall

Peninsula Medical School Theses

Introduction The author's interest in the therapeutic potential of the sting of nettles began with the presentation of two patients in his general practice surgery who were self-prescribing nettle sting for their arthritis pain. The publication of these two case reports produced responses from four other doctors about similar cases. Historical and contemporary research An extensive literature and database review produced few references from the medical literature but numerous anecdotal references from herbal and folklore sources of worldwide internal and external use of nettle since Roman times. The author has been asked to contribute two chapters on the historical and …

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P-Glycoprotein-Associated Anthracycline Resistance In B-Cll: Potential For Cytokine Modulation, Varinia Graciela Munoz-Ritchie Jan 2001

P-Glycoprotein-Associated Anthracycline Resistance In B-Cll: Potential For Cytokine Modulation, Varinia Graciela Munoz-Ritchie

Other Faculty of Health Theses

The phenomenon of multidrug resistance (MDR) in cancer cells is generally associated with P-glycoprotein (P-gp) expression and presents an obstacle to successful chemotherapy. Attempts to overcome P-gp-associated MDR using P-gp modulators, such as verapamil, have been hindered by their intrinsic in vivo toxicity. In 1991, however, Scala et al. demonstrated the alteration of P-gp function by interferon-alpha (IFN-α) in vitro at non-toxic in vivo concentrations, suggesting a basis for the use of IFN-α clinically in patients exhibiting P-gp-associated MDR. Drug resistance in B-CLL has been linked to the phenomenon of MDR, however, publications regarding this have been conflicting. The contrasting …

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Prophylaxis Of Disease Caused By Bacterial Pathogens Of Man, Richard William Titball Jan 2001

Prophylaxis Of Disease Caused By Bacterial Pathogens Of Man, Richard William Titball

Other Faculty of Health Theses

This thesis reports research undertaken which will lead to improved pretreatments and therapies for disease caused by Clostridium perfringens, Francisella tularensis, Yersinia pestis and Burkholderia pseudomallei. C. perfringens is thought to be the most widely distributed bacterial pathogen and is the most important Clostridial species associated with enteric disease in domesticated animals. During warfare C. perfringens has been a significant causes of mortality. Between 1 and 10% of wounded personnel developed gas gangrene during the 1st and 2nd world wars. The ability of the bacterium to cause a range of diseases is due largely to the differential production of toxins. …

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Cytokine Expression In Patients With B-Cell Chronic Lymphocytic Leukaemia, Anna Kaminski Jan 2001

Cytokine Expression In Patients With B-Cell Chronic Lymphocytic Leukaemia, Anna Kaminski

Other Faculty of Health Theses

B-cell chronic lymphocytic leukaemia (B-CLL) results from a clonal accumulation of CD5+ve B-lymphocytes. This expansion of B-lymphocytes is due to increased proliferation and extended survival secondary to decreased apoptosis. Both proliferation and apoptosis are regulated by a group of soluble proteins, termed cytokines, which are secreted by cells and play a key role in the regulation of immunological responses. In view of this, the role of cytokines in the pathogenesis of B-CLL was studied. Interleukin 4 (IL-4) is an anti-apoptotic cytokine which up-regulates bcl-2 in malignant B-lymphocytes. Peripheral blood samples, from untreated B-CLL patients were investigated, together with a group …

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A Study Of The Role Of Cytokines In Acute Pancreatitis In Man, Alison Marie Smithies Jan 2001

A Study Of The Role Of Cytokines In Acute Pancreatitis In Man, Alison Marie Smithies

Other Faculty of Health Theses

Introduction: Acute pancreatitis is an inflammatory disease with a diverse aetiology and variableclinical course. The IL-l gene cluster has been implicated in this disease.Aims: The aims of the study were to investigate polymorphisms of the genes encoded within the IL-lgene cluster in patients with acute pancreatitis and normal controls and to determine therelationship between the polymorphisms and protein levels.Methods: Genotype and allele frequencies were determined in controls (n=217) and patients withacute pancreatitis (n=137) using the polymerase chain reaction (PCR) followed by digestion withrestriction endonucleases where applicable. Protein levels were determined using in vitrostimulation of PBMCs followed by Enzyme Linked Immunosorbent …

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Study Of The Effect Of Turbulence On The Properties Of Flocculated Mud, Andrew Manning Jan 2001

Study Of The Effect Of Turbulence On The Properties Of Flocculated Mud, Andrew Manning

Other Faculty of Science and Engineering Theses

For the successful management of an estuary, an accurate simulation model predicting sediment transport patterns is a necessity. This requires a knowledge of the vertical mass settling flux (MSF), which is the product of the suspended particulate matter (SPM) concentration and the settling velocity (Ws). However the presence of cohesive sediments (i.e. mud) complicates this description due to the ability of mud particles to flocculate into larger aggregates (floes) which demonstrate faster settling velocities and lower effective densities (pe) than the component cohesive particles. The generation of turbulent shear stress (TSS) within the water column is regarded as having a …

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Implementing Marine Pollution Policy : Proposals For Change, Jonathan Peter Richards Jan 2001

Implementing Marine Pollution Policy : Proposals For Change, Jonathan Peter Richards

Other Faculty of Science and Engineering Theses

This study aims to determine the factors that affect the implementation of marine pollution policy, especially with regard to regulation of the hazardous substances which contaminate the marine environment- The purpose is to identify weaknesses in the current regulatory regime and to propose improvements. The study also aims to develop a new strategic framework for the implementation of the recent international policy commitments, which call for the complete cessation of discharges of hazardous substances into the marine environment by the year 2020. Furthermore, the study seeks to provide evidence to support or challenge current theories relating to regulation and policy …

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Developments And Benefits Of Liquid Feeding Through Fermentation For The Post-Weaned Pig, Colm Anthony Moran Jan 2001

Developments And Benefits Of Liquid Feeding Through Fermentation For The Post-Weaned Pig, Colm Anthony Moran

Other Faculty of Science and Engineering Theses

A programme of study was undertaken to assess the safety and palatability of fermented liquid feed. A series of laboratory experiments was conducted to select an inoculant capable of fermenting liquid feed at 20°C. Whilst combinations of cultures dropped the pH the most rapidly, the Lb. plantarum (PC) strain decreased the pH the lowest. A series of trials were conducted using a rifampicin mutant of Lb. plantarum (PC) to examine the fate of the starter culture. In an experiment using liquid milled wheat the addition of the starter culture resulted in an improvement in the inhibition of coliforms over the …

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Poetic Anatomy Of The Numinous Creative Passages Into The Self As Beloved, Partou Zia Jan 2001

Poetic Anatomy Of The Numinous Creative Passages Into The Self As Beloved, Partou Zia

Other Faculty of Arts, Humanities and Business Theses

This research is shaped by the actual experience of practice: as painter and writer. My preoccupation is with the nodal moment when conscious awareness is suspended, and both the corporal and psychic involvement in realising the work almost transport one to another zone of effectiveness. This zone, which I name as the poetic zone, is where the numinous enters the ordinary. The investigation for a space/place/moment that lies beyond the logic of acceptable discourse can help initiate and give shape to a new vocabulary - visual or literary. By orchestrating a methodology, which functions on several layers, I have endeavoured …

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The Resistance To Salt Of Brassica Sps. And Improved Resistance By Direct Selection And Mutagenesis, Manal Hassan Eed Jan 2001

The Resistance To Salt Of Brassica Sps. And Improved Resistance By Direct Selection And Mutagenesis, Manal Hassan Eed

Other Faculty of Science and Engineering Theses

Salinity is one of the most serious environmental stresses influencing agriculture drastically decreasing the production of crop plants throughout the world. Due to salinity thousands of hectares of agricultural land are going out of production annually. To cope with the salinity problem, there is keen interest in the development of crop plants displaying resistance to the effects of salinity. A series of experiments was carried out under controlled environmental conditions to determine salt resistance in Rapid Cycling Brassica species (RCB's) at germination early seedling and late growth stage. The effect of increasing salinity concentration was determined in vivo using a …

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Biomarkers Relevant To Oil And Gas Industrial Activities In Low Temperature Marine Ecosystems, Lionel Andre Yves Camus Jan 2001

Biomarkers Relevant To Oil And Gas Industrial Activities In Low Temperature Marine Ecosystems, Lionel Andre Yves Camus

School of Biological and Marine Sciences Theses

Because of its geographical location, the Arctic environment is considered as pristine. However, expanding industrial activities in the Arctic require assessment of the toxicity of chemicals at low temperature. Biomarkers defined as "biological responses to a chemical or chemicals that give a measure of exposure or toxic effect" were shown to be relevant to measure in situ impact of oil discharges. Most biomarker studies have been performed with temperate organisms. The Arctic is characterised by low stable temperature, strong seasonality in light, resulting in a short primary production in Spring. Therefore, indigenous organisms have developed specific adaptations to live with …

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Voronoi Cells, Fractal Dimensions And Fibre Composites, J. Summerscales, F. J. Guild, N. R.L. Pearce, P. M. Russell Jan 2001

Voronoi Cells, Fractal Dimensions And Fibre Composites, J. Summerscales, F. J. Guild, N. R.L. Pearce, P. M. Russell

School of Engineering, Computing and Mathematics

No abstract provided.

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Development Of Culture And Toxicity Testing Methods For The Freshwater Copepod Bryocamptus Zschokkei, Rebecca Jayne Brown Jan 2001

Development Of Culture And Toxicity Testing Methods For The Freshwater Copepod Bryocamptus Zschokkei, Rebecca Jayne Brown

School of Biological and Marine Sciences Theses

The aim of this thesis was to evaluate the use of a meiofaunal copepod as a test species for assessing the developmental and reproductive effects of toxicants relevant to freshwater ecosystems. The harpacticoid copepod Bryocamptus zschokkei was chosen as a candidate test species as it possesses several attributes (widespread distribution, small size and fast development times) that are considered pre-requisites for toxicity test organisms, and has previously been shown to be a sensitive component of the stream community to contaminant exposure. Prior to conducting toxicity tests with B. zschokkei, studies were performed to evaluate the effects of water hardness and …

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Mass Transport By Non-Linear Internal Waves On The Malin Shelf, Me Inall, Gi Shapiro, Tj Sherwin Jan 2001

Mass Transport By Non-Linear Internal Waves On The Malin Shelf, Me Inall, Gi Shapiro, Tj Sherwin

School of Biological and Marine Sciences

No abstract provided.

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Use Of The Nakhodka-Naoetsu Submarine Cable For Studying The Temporal Variability Of The Integral Water Transport In The Sea Of Japan, Na Pal'shin, Ll Vanyan, Rd Medzhitov, Gi Shapiro, Ma Evdoshenko, H Utada, H Shimizu, Y Tanaka Jan 2001

Use Of The Nakhodka-Naoetsu Submarine Cable For Studying The Temporal Variability Of The Integral Water Transport In The Sea Of Japan, Na Pal'shin, Ll Vanyan, Rd Medzhitov, Gi Shapiro, Ma Evdoshenko, H Utada, H Shimizu, Y Tanaka

School of Biological and Marine Sciences

No abstract provided.

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Maerl - A Spectacular Firth Of Clyde Habitat., Jm Hall-Spencer Jan 2001

Maerl - A Spectacular Firth Of Clyde Habitat., Jm Hall-Spencer

School of Biological and Marine Sciences

Pioneering marine biologists were drawn to study the diversity of organisms found in the Firth of Clyde throughout the 19th century. In 1885, naturalists decided to study this diversity in detail and moved a floating laboratory (the ‘Ark’) from the relatively impoverished waters of the Firth of Forth to Millport on the Isle of Cumbrae. The move proved a great success and one of the numerous advances made over the next decade was the discovery of local maerl communities. The proximity of a range of marine habitats located within sheltered waters clinched the decision to establish the first Scottish marine …

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Evaluation Of Haematococcus Pluvialis As A Natural Dietary Source Of The Carotenoid Astaxanthin For Rainbow Trout Flesh Pigmentation, Stephen Lagocki Jan 2001

Evaluation Of Haematococcus Pluvialis As A Natural Dietary Source Of The Carotenoid Astaxanthin For Rainbow Trout Flesh Pigmentation, Stephen Lagocki

School of Biological and Marine Sciences Theses

The efficacy of the lipid soluble carotenoid astaxanthin (biosynthesised as a secondary metabolite by the microalga Haematococcus pluvialis) as a source of pigment to enhance the aesthetic appeal of the flesh of farmed salmonid species has been investigated, using rainbow trout (Oncorhynchus mykiss) as a model. Accretion of astaxanthin within rainbow trout epaxial white muscle was primarily shown to be dependent on dietary inclusion and the type of diet used as a pigment carrier. Different dietary inclusion rates demonstrated a dose response. Cold pressed low oil and commercially extruded high oil diets containing similar astaxanthin concentration were tested, fish receiving …

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Molecular Characterisation Of A Two-Component Regulatory System From Burkholderia Pseudomallei, Magdy Elsayed Mahfouz Jan 2001

Molecular Characterisation Of A Two-Component Regulatory System From Burkholderia Pseudomallei, Magdy Elsayed Mahfouz

School of Biological and Marine Sciences Theses

Studies were undertaken to clone and characterise a two-component regulatory system from a clinical isolate (204) of the human and animal pathogen Burkholderia pseudomallei. A number of genomic libraries were constructed in E. coli host-vector systems and screened for the presence of a two-component system using oligonucleotide probes based on nucleotide sequence homology. Fragments of genomic DNA were cloned and sequenced and found to possess two open reading frames (ORFs) that overlap with a single nucleotide and are believed to encode a novel two-component regulatory system. A possible promoter region was identified upstream of the two ORFs, mrgR and mrgS, …

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The Uptake And Flux Of Dissolved Nitrogen In Marine Waters, Andrew Paul Rees Jan 2001

The Uptake And Flux Of Dissolved Nitrogen In Marine Waters, Andrew Paul Rees

School of Biological and Marine Sciences Theses

The biological uptake and transformation of inorganic nitrogen species is described for contrasting marine environments which include a sea loch, riverine plume, polar marginal ice-zone, continental shelf break, oligotrophic ocean and a mesoscale eddy. Uptake of nitrate and ammonium by phytoplankton has been determined using the stable isotope as a tracer and continuous flow stable isotope-ratio mass spectrometry. The analysis of dissolved and atmospheric nitrous oxide was made using electron capture detector gas chromatography in a novel configuration which also allowed for the simultaneous analysis of methane from a single sample. Significant advances in the study of the marine nitrogen …

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Anabolic Effect Of Estrogen Replacement On Bone In Postmenopausal Women With Osteoporosis: Histomorphometric Evidence In A Longitudinal Study., G Khastgir, J Studd, N Holland, J Alaghband-Zadeh, S Fox, J Chow Jan 2001

Anabolic Effect Of Estrogen Replacement On Bone In Postmenopausal Women With Osteoporosis: Histomorphometric Evidence In A Longitudinal Study., G Khastgir, J Studd, N Holland, J Alaghband-Zadeh, S Fox, J Chow

School of Biomedical Sciences

No abstract provided.

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Absorption And Utilisation Of Natural And Synthetic Astaxanthin Forms In Salmonid Nutrition, Daniel Allan White Jan 2001

Absorption And Utilisation Of Natural And Synthetic Astaxanthin Forms In Salmonid Nutrition, Daniel Allan White

School of Biological and Marine Sciences Theses

Consumer preference for commercially reared fish products that resemble their wild counterparts has resulted in the supplementation of pigments called carotenoids into aquafeeds to promote a pink-red colour in the flesh of salmonid fish. To date synthetic forms of these pigments have been commonly utilised to achieve this desired colouration, with the carotenoid astaxanthin being the regular choice for the feed manufacturer. However, increase in consumer demand for farmed fish products reared on natural feed additives has evoked an interest in natural sources of astaxanthin that could be successfully used to pigment salmonid fish efficiently. In the current study, the …

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Molecular Characterisation Of Burkholderia Pseudomallei, Clare Davies Jan 2001

Molecular Characterisation Of Burkholderia Pseudomallei, Clare Davies

School of Biological and Marine Sciences Theses

A programme of research was carried out to attempt the molecular characterisation of the human and animal pathogen, Burkholderia pseudomallei, the causative agent of melioidosis and the newly described avirulent species, B.thailandensis for comparative purposes. Melioidosis is still little understood, and so the clinical approach to the prevention and control of melioidosis must ultimately rest upon the basic understanding of the causative organism, particularly the pathogenic properties of B.pseudomallei. A range of B.pseudomallei and B.thailandensis isolates were cultured and the extracellular products were isolated and concentrated and an initial study conducted to identify potential target molecules for cloning. Those isolates …

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The Bioenergetics And Behaviour Of The Rainbow Trout (Oncorhynchus Mykiss) When Feeding On A Copper Contaminated Diet, Hamish Alistair Campbell Jan 2001

The Bioenergetics And Behaviour Of The Rainbow Trout (Oncorhynchus Mykiss) When Feeding On A Copper Contaminated Diet, Hamish Alistair Campbell

School of Biological and Marine Sciences Theses

The long-term effects of sub-lethal dietary Cu-exposure were investigated in relation to consequential energy shifts and resultant locomotory adaptation in 0. mykiss. This study represents the first to attempt to quantify the physiological cost of dietary heavy-metal exposure, the timing and extent of daily behavioural adaptation and resultant significance, in terms of ecologically important behaviours to the fish. Two long-term (2 & 3 months) dietary exposures of 730 mg Cu kgˉ¹ mg d.w. feed showed exposed fish to have a 3-fold increase in liver [Cu] and 10-fold increase in intestinal [Cu] compared to control fish. Consequently exposed fish elicited a …

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Physiological And Biochemical Factors Affecting Carotenoid Utilization In Salmonid Fish, Gregory Ian Page Jan 2001

Physiological And Biochemical Factors Affecting Carotenoid Utilization In Salmonid Fish, Gregory Ian Page

School of Biological and Marine Sciences Theses

Carotenoid utilization in rainbow trout (Oncorhynchus mykiss Walbaum) and Atlantic salmon (Salmo salar L.) has been investigated with respect to tissue distribution of carotenoids and the role of the liver on the bioavailability of the lipid soluble carotenoids, astaxanthin and canthaxanthin. Species-specific and tissue-specific accumulations were noted for astaxanthin and canthaxanthin in the rainbow trout and Atlantic salmon, possibly indicating fundamental differences in their utilization in these species. The liver and the kidney were revealed to be the major tissues involved in carotenoid metabolism in both rainbow trout and Atlantic salmon. Apparent digestibilities (-96% and -30% for rainbow trout and …

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Guanylyl Cyclase Activity Associated With Putative Bifunctional Integral Membrane Proteins In Plasmodium Falciparum, Dj Carucci, Aa Witney, Dk Muhia, Dc Warhurst, Et Al Jul 2000

Guanylyl Cyclase Activity Associated With Putative Bifunctional Integral Membrane Proteins In Plasmodium Falciparum, Dj Carucci, Aa Witney, Dk Muhia, Dc Warhurst, Et Al

School of Biomedical Sciences

We report here that guanylyl cyclase activity is associated with two large integral membrane proteins (PfGCalpha and PfGCbeta) in the human malaria parasite Plasmodium falciparum. Unusually, the proteins appear to be bifunctional; their amino-terminal regions have strong similarity with P-type ATPases, and the sequence and structure of the carboxyl-terminal regions conform to that of G protein-dependent adenylyl cyclases, with two sets of six transmembrane sequences, each followed by a catalytic domain (C1 and C2). However, amino acids that are enzymatically important and present in the C2 domain of mammalian adenylyl cyclases are located in the C1 domain of the P. …

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Effects Of Towed Demersal Fishing Gear On Biogenic Sediments: A 5-Year-Study, Jm Hall-Spencer Jun 2000

Effects Of Towed Demersal Fishing Gear On Biogenic Sediments: A 5-Year-Study, Jm Hall-Spencer

School of Biological and Marine Sciences

Experimental scallop fishing was carried out using towed commercial dredges on sediments deposited by unattached coralline algae in order to quantify their sensitivity to damage from current fishing practices. These biogenic sediments are patchily distributed in European coastal waters (to -30 m depth around the UK and to -120 m in the Mediterranean) and are of international conservation importance. This paper describes the short and long-term effects of scallop dredging on previously unfished and fished areas of biogenic algal sediment in SW Scotland. Sediment cores taken biannually from 1994-99 were used to assess live coralline abundance on marked test and …

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