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A New Hplc‐Elsd Method To Quantify Indican In Polygonum Tinctorium L. And To Evaluate Β‐Glucosidase Hydrolysis Of Indican For Indigo Production, Lg Angelini, E Campeol, S Tozzi, Et Al Jan 2003

A New Hplc‐Elsd Method To Quantify Indican In Polygonum Tinctorium L. And To Evaluate Β‐Glucosidase Hydrolysis Of Indican For Indigo Production, Lg Angelini, E Campeol, S Tozzi, Et Al

Peninsula Medical School

A method to quantify the indigo precursor indican (indoxyl-β-d-glucoside) in Polygonum tinctoriumL. has been developed. Plant material was extracted in deionized water, and indican was identified and quantified using high performance liquid chromatography (HPLC) coupled to an evaporative light scattering detector (ELSD). Results confirmed that with this method it is possible to measure indican content in a short time, obtaining reliable and reproducible data. Using this method, leaf indican content was quantified every 15 days during the growing season (from May to October) in P. tinctorium crops grown in a field experiment in Central Italy. Results showed that indican increased …

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Increased Brain Histamine H3 Receptor Expression During Hibernation In Golden-Mantled Ground Squirrels, T Sallmen, Af Lozada, Ov Anichtchik, Al Beckman, P Panula Jan 2003

Increased Brain Histamine H3 Receptor Expression During Hibernation In Golden-Mantled Ground Squirrels, T Sallmen, Af Lozada, Ov Anichtchik, Al Beckman, P Panula

School of Biological and Marine Sciences

BACKGROUND: Hibernation is a state of extremely reduced physiological functions and a deep depression of CNS activity. We have previously shown that the histamine levels increase in the brain during hibernation, as does the ratio between histamine and its first metabolite, suggesting increased histamine turnover during this state. The inhibitory histamine H3 receptor has both auto- and heteroreceptor function, rendering it the most likely histamine receptor to be involved in regulating the activity of histamine as well as other neurotransmitters during hibernation. In view of accumulating evidence that there is a global depression of transcription and translation during hibernation, of …

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Problems Facing Maerl Conservation In Brittany, J Grall, Jm Hall-Spencer Jan 2003

Problems Facing Maerl Conservation In Brittany, J Grall, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Substratum Heterogeneity Of Dredged Vs Un-Dredged Maerl Grounds, Na Kamenos, Pg Moore, Jm Hall-Spencer Jan 2003

Substratum Heterogeneity Of Dredged Vs Un-Dredged Maerl Grounds, Na Kamenos, Pg Moore, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Supporting Biosciences In The Nursing Curriculum: Development And Evaluation Of An Online Resource, Ka Gresty, Dre Cotton Jan 2003

Supporting Biosciences In The Nursing Curriculum: Development And Evaluation Of An Online Resource, Ka Gresty, Dre Cotton

School of Biomedical Sciences

Aims. The aim of this project was to develop and evaluate an online resource designed to improve the biosciences knowledge of preregistration nursing students. Background. A number of studies have identified lack of biological subject knowledge and anxiety about studying biosciences as serious problems for nursing students. The availability of a contextualized biological information resource prior to and early in their studies might help to reduce this fear and anxiety. Methods. The project used an action research approach, involving an initial analysis of the extent of the problems with biosciences encountered by our nursing students, followed by the development and …

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The Insecticidal Properties Of A Garlic Oil, With Special Reference To Its Use Against Two Dipteran Pests, Gareth Michael Prowse Jan 2003

The Insecticidal Properties Of A Garlic Oil, With Special Reference To Its Use Against Two Dipteran Pests, Gareth Michael Prowse

School of Biological and Marine Sciences Theses

The potential for a quantitatively produced garlic oil for use as an insecticide was investigated. The study assessed the garlic oils efficacy in the laboratory and in the field, as well as its physiological effect on three key enzymes noted for their involvement either in toxicity, or detoxication of exogenous toxins in two Dipteran pests; Delia radicum (L.) and Musca domestica (L.). The garlic oil absorbed onto wood flour pellets (prills) had no significant repellent effect on D. radicum, in choice tests when presented with artificial oviposition sites. Exposure of 24hr old D. radicum eggs to garlic prills placed on …

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Studies On The Filamentous Gliding Bacteria Vitreoscilla Stercoraria, Laura Frances Biggs Jan 2003

Studies On The Filamentous Gliding Bacteria Vitreoscilla Stercoraria, Laura Frances Biggs

School of Biological and Marine Sciences Theses

Strains of Vitreoscilla stercoraria were isolated from the environment and characterised. Cell width, motility and requirement of each strain for sodium chloride were investigated. Two strains were selected for further study and the effect of monensin and FCCP on growth of the strains was investigated. One strain of Vitreoscilla (LB13) was chosen for further study, cells from strain LB 13 were found to be 1.38 µm ± 0.041 (± 1 SEM, n=10) wide, were motile by gliding and had an optimum requirement for sodium chloride for growth of 43 mM. The organism was grown in batch culture and respiratory membranes …

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Dietary Availability And Retention Of Selected Minerals Associated With The Intensive Production Of Rainbow Trout (Oncorhynchus Mykiss), Donna Leanne Snellgrove Jan 2003

Dietary Availability And Retention Of Selected Minerals Associated With The Intensive Production Of Rainbow Trout (Oncorhynchus Mykiss), Donna Leanne Snellgrove

School of Biological and Marine Sciences Theses

This research programme aimed to review the nutritional requirements for the main minerals, (namely calcium, phosphorus, magnesium and zinc) formulated in commercial diets that are essential for the health and growth performance for salmonid fish. This was undertaken with the aim of improving our knowledge of their physiology, metabolism and fate in the rainbow trout, Oncorhynchus mykiss. Phosphorous (P) featured strongly in this work due to its adverse role in pollution and the environmental impact of intensive fish farming. The first chapter surveyed the gross nutritional requirements of fish and focused on the mineral requirements in particular. Typically the P …

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Liquid Feeding Of Pigs 1: Potential For Reducing Environmental Impact And For Improving Productivity, Peter Brooks, Jane Davina Beal Jan 2003

Liquid Feeding Of Pigs 1: Potential For Reducing Environmental Impact And For Improving Productivity, Peter Brooks, Jane Davina Beal

More Faculty of Science and Engineering Research

No abstract provided.

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A Longitudinal Study Of The Effect Of Subcutaneous Estrogen Replacement On Bone In Young Women With Turner's Syndrome, G Khastgir, Jww Studd, Sw Fox, J Jones, J Aghband-Zadeh, Jwm Chow Jan 2003

A Longitudinal Study Of The Effect Of Subcutaneous Estrogen Replacement On Bone In Young Women With Turner's Syndrome, G Khastgir, Jww Studd, Sw Fox, J Jones, J Aghband-Zadeh, Jwm Chow

School of Biomedical Sciences

No abstract provided.

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The Possible Role Of Tgf-Beta-Induced Suppressors Of Cytokine Signaling Expression In Osteoclast/Macrophage Lineage Commitment In Vitro, Sw Fox, Sj Haque, Ac Lovibond, Tj Chambers Jan 2003

The Possible Role Of Tgf-Beta-Induced Suppressors Of Cytokine Signaling Expression In Osteoclast/Macrophage Lineage Commitment In Vitro, Sw Fox, Sj Haque, Ac Lovibond, Tj Chambers

School of Biomedical Sciences

No abstract provided.

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Tgf-Beta-Induced Socs3 Expression Augments Tnf-Alpha-Induced Osteoclast Formation, Ac Lovibond, Sj Haque, Tj Chambers, Sw Fox Jan 2003

Tgf-Beta-Induced Socs3 Expression Augments Tnf-Alpha-Induced Osteoclast Formation, Ac Lovibond, Sj Haque, Tj Chambers, Sw Fox

School of Biomedical Sciences

No abstract provided.

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An Investigation Of The Phototransduction Cascade And Temporal Characteristics Of The Retina Of The Cuttlefish, Sepia Officinalis, Lisa Nelson Jan 2003

An Investigation Of The Phototransduction Cascade And Temporal Characteristics Of The Retina Of The Cuttlefish, Sepia Officinalis, Lisa Nelson

School of Biological and Marine Sciences Theses

Cephalopods have extremely well developed visual systems which are of particular interest due to the well known morphological similarity of the cephalopod eye to the vertebrate eye. This similarity ends at the level of the photoreceptors where vertebrates and invertebrates have been found to use different intracellular second messengers. Although the effect of extracellular ion manipulation on the light response has been examined and some very useful biochemical studies carried out, the pathway has not been investigated by the use of pharmacological intervention; a method which has proved to be useful in other preparations. This study examines various properties of …

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Complete Analysis Of The B‐Cell Response To A Protein Antigen, From In Vivo Germinal Centre Formation To 3‐D Modelling Of Affinity Maturation, Cl Adams, Mkl Macleod, Milner‐White E James, R Aitken, P Garside, Di Stott Jan 2003

Complete Analysis Of The B‐Cell Response To A Protein Antigen, From In Vivo Germinal Centre Formation To 3‐D Modelling Of Affinity Maturation, Cl Adams, Mkl Macleod, Milner‐White E James, R Aitken, P Garside, Di Stott

Peninsula Medical School

SummarySomatic hypermutation of immunoglobulin variable region genes occurs within germinal centres (GCs) and is the process responsible for affinity maturation of antibodies during an immune response. Previous studies have focused almost exclusively on the immune response to haptens, which may be unrepresentative of epitopes on protein antigens. In this study, we have exploited a model system that uses transgenic B and CD4+ T cells specific for hen egg lysozyme (HEL) and a chicken ovalbumin peptide, respectively, to investigate a tightly synchronized immune response to protein antigens of widely differing affinities, thus allowing us to track many facets of the development …

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Images Of Engineering: An Investigation Of Gender And Attitudes Towards Engineering, Liz Hodgkinson Jan 2003

Images Of Engineering: An Investigation Of Gender And Attitudes Towards Engineering, Liz Hodgkinson

School of Law, Humanities and Social Sciences Theses

The research presented in this thesis used a mixed method approach to investigate the attitudes of sixth-form students in two British cities, towards engineering as a career, with the aim of finding out which factors encourage or discourage young people from becoming engineers, and whether these differ for males and females. The study can be set in the context of the declining popularity of engineering as a career choice for males and the continuing under-representation of females, for whom engineering is a non-traditional career choice. The principal research hypothesis was that negative images of engineering discourage girls and many boys …

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Identification Of A Second Proliferating Cell Nuclear Antigen In The Human Malarial Pathogen Plasmodium Falciparum, J-L Li, Av Warren, Ls Cox Dec 2002

Identification Of A Second Proliferating Cell Nuclear Antigen In The Human Malarial Pathogen Plasmodium Falciparum, J-L Li, Av Warren, Ls Cox

School of Biomedical Sciences

Proliferating cell nuclear antigen seems to exist as a single form in higher eukaryotic cells and plays multiple roles in nucleic acid metabolism. We have identified a second additional proliferating cell nuclear antigen (PfPCNA2) in Plasmodium falciparum on the basis of several lines of evidence. (1) PfPCNA2, consisting of 264 amino acid residues with a predicted molecular mass of 30.2kDa, shares only 29% identity and 53% similarity with PfPCNA1 at the amino acid level. (2) Southern blot analyses revealed that the hybridisation pattern of the Pfpcna2 gene is completely different from that of the Pfpcna1 gene. (3) Chromosomal localisation studies …

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Visualisation Of Synchronous Firing In Multi-Dimensional Spike Trains, L Stuart, M Walter, R Borisyuk Oct 2002

Visualisation Of Synchronous Firing In Multi-Dimensional Spike Trains, L Stuart, M Walter, R Borisyuk

School of Engineering, Computing and Mathematics

The gravity transform algorithm is used to study the dependencies in firing of multi-dimensional spike trains. The pros and cons of this algorithm are discussed and the necessity for improved representation of output data is demonstrated. Parallel coordinates are introduced to visualise the results of the gravity transform and principal component analysis (PCA) is used to reduce the quantity of data represented whilst minimising loss of information.

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The Processing Of Holliday Junctions By Blm And Wrn Helicases Is Regulated By P53, Q Yang, R Zhang, Xw Wang, Ea Spillare, Et Al Aug 2002

The Processing Of Holliday Junctions By Blm And Wrn Helicases Is Regulated By P53, Q Yang, R Zhang, Xw Wang, Ea Spillare, Et Al

School of Biomedical Sciences

BLM, WRN, and p53 are involved in the homologous DNA recombination pathway. The DNA structure-specific helicases, BLM and WRN, unwind Holliday junctions (HJ), an activity that could suppress inappropriate homologous recombination during DNA replication. Here, we show that purified, recombinant p53 binds to BLM and WRN helicases and attenuates their ability to unwind synthetic HJ in vitro. The p53 248W mutant reduces abilities of both to bind HJ and inhibit helicase activities, whereas the p53 273H mutant loses these abilities. Moreover, full-length p53 and a C-terminal polypeptide (residues 373-383) inhibit the BLM and WRN helicase activities, but phosphorylation at Ser(376) …

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Saving Europe's Coral Reefs, Jm Hall-Spencer Jun 2002

Saving Europe's Coral Reefs, Jm Hall-Spencer

School of Biological and Marine Sciences

No abstract provided.

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Numerical Experiments On The Breaking Of Solitary Internal Waves Over A Slope-Shelf Topography, Vasiliy Vlasenko Jun 2002

Numerical Experiments On The Breaking Of Solitary Internal Waves Over A Slope-Shelf Topography, Vasiliy Vlasenko

School of Biological and Marine Sciences

No abstract provided.

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Our Very Own Coral Reef Crisis, J Hall-Spencer Jun 2002

Our Very Own Coral Reef Crisis, J Hall-Spencer

School of Biological and Marine Sciences

The past decade has seen trawling operations expand along the edge of the North East Atlantic continental shelf, as stocks of shelf-dwelling species such as cod have declined. As a substitute, markets are being developed for very strange-looking deep-water species such as roundnose grenadier (Coryphaenoides rupestris), orange roughy (Hoplostethus atlanticus), black scabbard fish (Aphanopus carbo) and deep-sea sharks (Centrophorus squamosus and Centroscymnus coelolepis). The problem is that this expansion in deep-water fisheries goes on unregulated, and it is causing long-term disturbance to seabed habitats and fish stocks alike

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Trawling Damage To Northeast Atlantic Ancient Coral Reefs, Jason Hall-Spencer, Jh Fossa, Valerie Allain Mar 2002

Trawling Damage To Northeast Atlantic Ancient Coral Reefs, Jason Hall-Spencer, Jh Fossa, Valerie Allain

School of Biological and Marine Sciences

10.1098/rspb.2001.1910

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Pitch Estimation For Noisy Speech, Azar Khurshid Jan 2002

Pitch Estimation For Noisy Speech, Azar Khurshid

School of Engineering, Computing and Mathematics Theses

In this dissertation a biologically plausible system of pitch estimation is proposed. The system is designed from the bottom up to be robust to challenging noise conditions. This robustness to the presence of noise in the signal is achieved by developing a new representation of the speech signal, based on the operation of damped harmonic oscillators, and temporal mode analysis of their output. This resulting representation is shown to possess qualities which are not degraded in presence of noise. A harmonic grouping based system is used to estimate the pitch frequency. A detailed statistical analysis is performed on the system, …

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Investigation Into The Control Of An Upper-Limb Myoelectric Prosthesis, Steven Michael Roberts Jan 2002

Investigation Into The Control Of An Upper-Limb Myoelectric Prosthesis, Steven Michael Roberts

School of Engineering, Computing and Mathematics Theses

This thesis presents research that extends current knowledge in the area of upper-limb prosthesis design and control. A study of myoelectric signals (MES)'s using both NHS and other equipment has resulted in identification of the signal source and transmission/detection issues. A globally comprehensive and up to date survey of myoelectric research has revealed new and long-term research paths. This thesis challenges the old model in interpreting the MES signals by providing and collecting evidence to suggest a new approach to future investigation. The historical description of a stochastic, non-deterministic MES has been shown by this research to be incomplete. An …

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Grazing Management And Plant Community Composition On Bodmin Moor, Gavin Stewart Jan 2002

Grazing Management And Plant Community Composition On Bodmin Moor, Gavin Stewart

School of Geography, Earth and Environmental Sciences Theses

The research presented in this thesis was focused on aspects of the dynamic response of upland vegetation to grazing, to allow evaluation of the suitability of Countryside Stewardship (CS) management for the rehabilitation of dwarf-shrub cover in the upland landscape of Bodmin Moor. Initial chapters review the ecological character of Bodmin Moor, grazing management and vegetation in upland habitats, and succession in relation to grazing. Chapter Five provides the first extensive and detailed phytosociological investigation of the vegetation of Bodmin Moor-providing a baseline for further work. It also examines the spatial distribution of the plant communities in relation to environmental …

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Determination Of Additives In Fuels Using Automated Flow Injection Analysis With Chemiluminescence Detection, Philip James Fletcher Jan 2002

Determination Of Additives In Fuels Using Automated Flow Injection Analysis With Chemiluminescence Detection, Philip James Fletcher

School of Geography, Earth and Environmental Sciences Theses

The overall objective of this thesis was to develop field deployable instrumentation for the selective, sensitive determination of additives in diesel fuels using flow injection with chemiluminescence detection. The target analytes were the detergent dodecylamine and the lubricity additive P655. Chapter One describes the types of additives that are used in fully formulated diesel fuels in order to improve performance and outlines the need for robust analytical methods to be able to detect their presence / absences in fuels at the point of distribution, i.e. at the petrol pump. Flow injection (FI), and chemiluminescence (CL) are described as suitable techniques …

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In Situ Monitoring And Biogeochemical Cycling Of Nutrients In Estuarine Waters, Paulo Cesar Ferreira Da Costa Gardolinski Jan 2002

In Situ Monitoring And Biogeochemical Cycling Of Nutrients In Estuarine Waters, Paulo Cesar Ferreira Da Costa Gardolinski

School of Geography, Earth and Environmental Sciences Theses

This thesis describes the use of in situ and laboratory techniques for monitoring nitrate, phosphate and master variables in the environment. Chapter One presents a general overview of nutrients, how they are essential for aquatic biota, their general characteristics and the importance of their behaviour in estuaries. Commonly used analytical methods for nutrient determinations in natural waters are also evaluated. Chapter Two reports the use of chemometrics to determine trends in historical time-series physicochemical datasets {e.g. nitrate+nitrite, phosphate, river flow, precipitation, suspended solids, water temperature and chlorophyll a) from the Tamar catchment, UK. The results provided useful information about correlations …

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The Influence Of Surfactants On The Sorption Of Phenanthrene In Natural Waters, Tracey Louise Jones-Hughes Jan 2002

The Influence Of Surfactants On The Sorption Of Phenanthrene In Natural Waters, Tracey Louise Jones-Hughes

School of Geography, Earth and Environmental Sciences Theses

Polycyclic aromatic hydrocarbons (PAHs) are widely recognised as harmful, persistent organic pollutants, whilst surfactants are more easily degraded but their ubiquitous use both domestically and industrially ensures their presence in natural waters. Owing to both their hydrophobic and hydrophilic properties, surfactants are capable of both adsolubilisation and solubilisation of co-contaminants, hence, their presence in natural waters is considered extremely significant. The purpose of this research was to determine how surfactants and PAHs influence each other in estuaries where both are co-disposed. This study is the first to employ environmentally realistic concentrations of surfactants and to use natural particles in order …

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Unresolved Complex Mixtures Of Aromatic Hydrocarbons In The Marine Environment : Toxicity, Solubility And Photodegradation Studies, Emma Louise Smith Jan 2002

Unresolved Complex Mixtures Of Aromatic Hydrocarbons In The Marine Environment : Toxicity, Solubility And Photodegradation Studies, Emma Louise Smith

School of Geography, Earth and Environmental Sciences Theses

Unresolved complex mixtures (UCMs) of aromatic hydrocarbons have been found in a wide range of environmental matrices at high concentrations. However, limited consideration has been given to the potential detrimental effects of the accumulation of these compounds in the marine environment. In particular, there is a need to evaluate these compounds in the light of recent evidence that points to the long term effects of oil in the marine environment. The overall aim of this work was therefore to investigate unresolved complex mixtures of aromatic hydrocarbons in the marine environment with particular emphasis on assessment of toxicity, aqueous solubility and …

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The Development And Study Of Chelating Substrates For The Separation Of Metal Ions In Complex Sample Matrices, James Cowan Jan 2002

The Development And Study Of Chelating Substrates For The Separation Of Metal Ions In Complex Sample Matrices, James Cowan

School of Geography, Earth and Environmental Sciences Theses

The fabrication and study of high performance chelating substrates for the separation of trace metals using a single column under both isocratic and gradient elutions were investigated. Neutral polystyrene based resins from a variety of manufacturers including a hypercrosslinked resin (MN 200) were functionalised via impregnation with chelating dyestuffs or dynamically modified with small, low molecular weight organic molecules by physical adsorption and chemisorption processes respectively. Improvements in the impregnation of substrates were developed, based upon ultrasonic agitation, along with improvements in the detection of metal ions by the use of a noise reduction system, eluent clean-up procedures and large …

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