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The Role Of Biological Interactions In Modifying The Effects Of Climate Change On Intertidal Assemblages, Phillipa Jane Moore Jan 2005

The Role Of Biological Interactions In Modifying The Effects Of Climate Change On Intertidal Assemblages, Phillipa Jane Moore

School of Biological and Marine Sciences Theses

The geographic distribution of most species is expected to alter as a consequence of global climate change. Predictions for the extent of these range shifts are frequently based on anticipated changes in temperature using a 'climate envelope' approach, which oversimplifies predictions because it does not consider interactions with other physical and biological factors. The aim of this thesis was to investigate how biological interactions modulate species responses to climate change. On many rocky shores in the NE Atlantic the interaction between limpets, barnacles and canopy forming macroalgae have an important role in structuring rocky shore communities. In particular, limpets control …

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Mesoscale Circulation In The Black Sea : A Study Combining Numerical Modelling And Observations, Cecilia Elizabeth Enriquez Ortiz Jan 2005

Mesoscale Circulation In The Black Sea : A Study Combining Numerical Modelling And Observations, Cecilia Elizabeth Enriquez Ortiz

School of Geography, Earth and Environmental Sciences Theses

Mesoscale dynamics play a major role in the general circulation throughout the ocean. Mesoscale eddies promote the exchange of material and physical properties between different areas of the ocean such as continental shelves and the deep seas. Despite the increasing number of studies on mesoscale processes, there are further important questions unanswered concerning the origin and evolution of eddies, the mechanisms enhancing mesoscale activity and the detachment of eddies from the coast. The present research contributes to the understanding of the mesoscale circulation in the Black Sea basin by combining hydrodynamic numerical modelling with observational data analysis. Within this research: …

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Medium-Term (Months To Years) Morphodynamic Modelling Of A Complex Estuarine System, Marcos Eduardo Cordeiro Bernardes Jan 2005

Medium-Term (Months To Years) Morphodynamic Modelling Of A Complex Estuarine System, Marcos Eduardo Cordeiro Bernardes

School of Geography, Earth and Environmental Sciences Theses

This contribution focuses on the medium-term (months to years) morphodynamic modelling of natural estuaries. A 2D morphodynamic model based on the Telemac system was calibrated and validated using extensive field measurements' at Teignmouth (UK). Statistical tools indicate that the model is capable of predicting the observed hydrodynamics with 'good' accuracy, given that measurement noise is removed. Despite some qualitative agreement, morphological predictions show a more limited skill; consistent with the current 'state of the art' in this area of scientific research. The typical long simulation times associated with process-based morphodynamic models are optimised through the successful implementation of an input …

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A Study Of Mediterranean Bluefin Tuna (Thunnus Thynnus L.) With Reference To Stock Identification And Management Strategies, Andreina Fenech Farrugia Jan 2005

A Study Of Mediterranean Bluefin Tuna (Thunnus Thynnus L.) With Reference To Stock Identification And Management Strategies, Andreina Fenech Farrugia

School of Geography, Earth and Environmental Sciences Theses

The management of bluefin tuna (Thunnus thynnus) in the north Atlantic has been based on the assumption that there are two separate stocks (an eastern Atlantic stock, including the Mediterranean Sea and a western Atlantic stock). This hypothesis has never been scientifically confirmed. This study provides evidence of unique stock characteristics of the bluefin tuna population targeted specifically in the Mediterranean and aims at showing that it is a single stock suitable for its own management regime. This has been done through the study of the biological parameters of bluefin tunas sampled in the Mediterranean, including biometric relationships, age determination, …

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Determination Of Dissolved Iron Speciation In The North East Atlantic Ocean By Flow Injection Chemiluminescence, Simon Ussher Jan 2005

Determination Of Dissolved Iron Speciation In The North East Atlantic Ocean By Flow Injection Chemiluminescence, Simon Ussher

School of Geography, Earth and Environmental Sciences Theses

The knowledge of iron biogeochemistry is constrained by paucity in the understanding of its uptake, transport and the partitioning of the element between different phases, redox states and coordination sites. The work presented in this thesis describes the optimisation and evaluation of a Flow Injection Chemiluminescence (FICL) method for the shipboard determination of dissolved Fe(II) species (< 0.2 µm) in seawater. This includes results from two ship-board trials and a study of the effects of model ligands on iron redox speciation measurements in natural waters. The method was also used to determine the distribution of dissolved iron species (< 0.2 µm) in two contrasting study areas in the North East Atlantic Ocean and for a study of aerosol iron dissolution in seawater. The FI-CL method was evaluated and was found to be robust and sensitive, to have low limits o f detection (5-12 pM) and short analysis times 3 min) suitable for the high resolution spatial and temporal sampling required for shipboard analysis of Fe(II). A study of the effects of model ligands on Fe(II) determination revealed no conclusive evidence for significant interference from organic molecules on the method but Fe(III) in the presence of certain organic molecules had the potential to cause positive and negative interference in aqueous samples. Field survey results obtained for a transect between the Bay of Biscay to the coast of the Netherlands, showed enrichment of dissolved iron (0.7 - 2 nM) on the European continental shelf in March 2002. Near the shelf break, the iron enriched shelf waters were separated from low iron open ocean surface waters (0.15 - 0.4 nM) by a well-defined mixing gradient. Elevated dissolved Fe(II) concentrations (> 100 pM) were observed at the shelf break and during a solar radiation maximum in the coastal waters of the southern North Sea. These features were attributed to the dissolution of Fe(II) from anoxic sediments and photoreduction of iron from dissolved and suspended …

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Modelling The Water Quality Of The Patos Lagoon, Brazil, Deborah Ann Tyrrell Jan 2005

Modelling The Water Quality Of The Patos Lagoon, Brazil, Deborah Ann Tyrrell

School of Geography, Earth and Environmental Sciences Theses

A two-dimensional depth integrated finite element modelling suite comprising the flow model TELEN4AC-2D and the water quality model WQFLOW-2D has been calibrated to simulate the physics and chemistry of the Patos Lagoon and Estuary system in southern Brazil for the investigation of nutrients, primary production and faecal bacteria. The model has been evaluated for use as a predictive tool to aid the decision making process for the rehabilitation and management of the shallow embayment of Saco da Mangueira adjacent to the city of Rio Grande in the lower Patos Estuary. This bay is one of several shallow areas bordering the …

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The Dynamics Of A Tidal Intrusion Front In A Natural Estuary: Effects On Multibeam Sonar Accuracy, Richard Holman Collingwood Thain Jan 2005

The Dynamics Of A Tidal Intrusion Front In A Natural Estuary: Effects On Multibeam Sonar Accuracy, Richard Holman Collingwood Thain

School of Geography, Earth and Environmental Sciences Theses

This research has utilised high-resolution measurements of density and velocity to investigate the formation of a transient tidal intrusion front in a narrow, macrotidal estuary, and model the impact of such a frontal system on the accuracy of multibeam sonar surveys. The front was found to form during spring tides, when the barotropic inflow was sufficient to arrest the buoyant outflow from the estuary. This has been shown to be driven by changes in channel width and depth, creating a hydraulic control point. These changes in topography are demonstrated to interact with the flow m a similar manner to theoretical …

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Development Of A Non-Invasive Electrophysiological System For Measuring The Auditory Capability Of Marine Animals, Jonathan Murray Lovell Jan 2005

Development Of A Non-Invasive Electrophysiological System For Measuring The Auditory Capability Of Marine Animals, Jonathan Murray Lovell

School of Geography, Earth and Environmental Sciences Theses

The following work describes the development and application of a neurological system to definitively profile the auditory responses of aquatic animals, presented as audiograms showing hearing threshold verses sound frequency. The accuracy of such information is essential for the optimisation of bio-technical devices such as the Acoustic Fish Deterrent (AFD) barrier deployed in the Illinois River to prevent the migration of non-indigenous Asian carp into Lake Michigan, and in the impact assessment of anthropogenic underwater sounds on the hearing of cetaceans and other marine animals. The ensuing Auditory Brainstem Response (ABR) electrophysiological recording technique developed at the University of Plymouth …

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Analysis Of Pharmaceuticals And Biomolecules Using Hplc Coupled To Icp-Ms And Esi-Ms, Andrew James Cartwright Jan 2005

Analysis Of Pharmaceuticals And Biomolecules Using Hplc Coupled To Icp-Ms And Esi-Ms, Andrew James Cartwright

School of Geography, Earth and Environmental Sciences Theses

The work described within this thesis explores the use of HPLC coupled with ICPMS and ESI-MS in order to develop novel methods which overcome specific analytical challenges in the pharmaceutical industry. A membrane desolvation interface has been evaluated for coupling high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Desolvation of the sample prior to reaching the plasma was shown to facilitate a versatile coupling of the two instrumental techniques, enabling chromatographic eluents containing up to 100 % organic to be used. This interface also allowed gradient elution to be used with ICP-MS. Tris(2,4,6-trimethoxyphenyl)phosphonium propylamine bromide (TMPP) …

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Techniques For Studying The Biogeochemistry Of Nutrients In The Tamar Catchment, Utra Mankasingh Jan 2005

Techniques For Studying The Biogeochemistry Of Nutrients In The Tamar Catchment, Utra Mankasingh

School of Geography, Earth and Environmental Sciences Theses

Chapter One describes nitrogen and phosphorus species in the aquatic environment, their role in eutrophication, current legislation relevant to nutrient water quality and catchment management and the role of predictive modelling of nutrient export with respect to the management of river catchments. It also summarises analytical techniques for the determination of nitrogen and phosphorus species in natural waters and the use of generic ecotoxicological assays to link nutrient water quality and organism health. Data integrity is essential to biogeochemical studies that inform scientific research and environmental management. Reliable, accurate data permit valid conclusions to be drawn. The quality assurance and …

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Use Of Depth Perception For The Improved Understanding Of Hydrographic Data, Runar Ostnes Jan 2005

Use Of Depth Perception For The Improved Understanding Of Hydrographic Data, Runar Ostnes

School of Geography, Earth and Environmental Sciences Theses

This thesis has reviewed how increased depth perception can be used to increase the understanding of hydrographic data First visual cues and various visual displays and techniques were investigated. From this investigation 3D stereoscopic techniques prove to be superior in improving the depth perception and understanding of spatially related data and a further investigation on current 3D stereoscopic visualisation techniques was carried out. After reviewing how hydrographic data is currently visualised it was decided that the chromo stereoscopic visualisation technique is preferred to be used for further research on selected hydrographic data models. A novel chromo stereoscopic application was developed …

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Maltese Fisheries And The Sustainability Of Resources Around The Maltese Islands, Matthew Camilleri Jan 2005

Maltese Fisheries And The Sustainability Of Resources Around The Maltese Islands, Matthew Camilleri

School of Geography, Earth and Environmental Sciences Theses

Despite the socio-cultural importance of Maltese fisheries, a very limited number of studies and reports on the industry have been published, and scientific studies on the interaction between the Maltese fishing fleet and the fisheries resources exploited have never been carried out. Data collection schemes to monitor Maltese fisheries were also found to be extremely limited, however, this study has analysed the information arising from recently initiated data collection programmes, coordinated by the author, related to the fleet, its activities and the resources exploited; these programmes were namely a fishing fleet census, catch and effort sampling schemes and trawl surveys. …

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Small Island Developing States, Sustainability And The Caribbean Sea, Asha Singh Jan 2005

Small Island Developing States, Sustainability And The Caribbean Sea, Asha Singh

School of Geography, Earth and Environmental Sciences Theses

This study encompasses twenty-seven SIDS and the Caribbean Sea. In order to detennine the pressure on the sea from anthropogenic activities both terrestrial and marine, four major components were investigated. These are (a) how land use activities on the islands are affecting the Sea (b) the effects of coastal and marine based activities on this marine area (c) the influences of natural events on the Caribbean Sea and the SIDS (d) how the region is responding to minimise the pressures on the sea via policies and programmes. In the first component, the DPSIR in combination with GIS was applied to …

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Phosphorus Speciation In Soil Leachate Using Field-Flow Fractionation And Flow Injection Analysis, Laura Jane Gimbert Jan 2005

Phosphorus Speciation In Soil Leachate Using Field-Flow Fractionation And Flow Injection Analysis, Laura Jane Gimbert

School of Geography, Earth and Environmental Sciences Theses

Colloidal material (0.001 - 1 um) in soil leachate and agricultural drainage waters is an important route for the transport of contaminants such as phosphorus from land to catchments. Excessive phosphorus concentrations can result in eutrophication of natural waters. To be able to characterise the colloidal material, in terms of size distribution, a mild and relatively new separation technique field-flow fractionation (FFF) can be used to fractionate complex colloidal samples. By combining FFF and flow injection analysis (FIA) more detailed physico-chemical information on phosphorus species in soil leachates and agricultural runoff waters can be obtained. Chapter 1 describes the methods …

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A Computational Model Of Auditory Feature Extraction And Sound Classification, Martin Coath Jan 2005

A Computational Model Of Auditory Feature Extraction And Sound Classification, Martin Coath

Other Faculty of Science and Engineering Theses

This thesis introduces a computer model that incorporates responses similar to those found in the cochlea, in sub-corticai auditory processing, and in auditory cortex. The principle aim of this work is to show that this can form the basis for a biologically plausible mechanism of auditory stimulus classification. We will show that this classification is robust to stimulus variation and time compression. In addition, the response of the system is shown to support multiple, concurrent, behaviourally relevant classifications of natural stimuli (speech). The model incorporates transient enhancement, an ensemble of spectro - temporal filters, and a simple measure analogous to …

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Environmental Assessment Of Biogeochemical Cycling Of Dissolved Organic Carbon (Doc) And Nitrogen (Don) In Natural Waters, El-Sayed A. Badr Jan 2005

Environmental Assessment Of Biogeochemical Cycling Of Dissolved Organic Carbon (Doc) And Nitrogen (Don) In Natural Waters, El-Sayed A. Badr

Other Faculty of Science and Engineering Theses

Increases in human population and activities have lead to significantly enhanced inputs of carbon and nitrogen fiom both point and difiuse sources to rivers, estuaries, and coastal seas, altering the global carbon and nitrogen biogeochemical cycles. This increased load has had a marked ecological impact globally, with detrimental changes to primary production, conununity stricture and water quality. Understandmg the nature and cycling of dissolved organic carbon (DOC) and nitrogen (DON), significant components of the global carbon and nitrogen cycles, in estuaries will provide better estimates of C and N transport to coastal and ocean waters. This study involves: (1) optimisation …

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Using Interactive Software As A Conceptual Tool: An Examination Of Cognition In Improvised Musical Performance, Timothy Thomas Sayer Jan 2005

Using Interactive Software As A Conceptual Tool: An Examination Of Cognition In Improvised Musical Performance, Timothy Thomas Sayer

Other Faculty of Arts, Humanities and Business Theses

Viewing musical improvisation in the light of psychology and cognitive science, this thesis will explicate the rationale behind the development of a software based audiovisual interface for use in improvised solo instrumental performance. The evolution of the performance environment is presented along with the theories and concepts that have shaped its progress. The opening chapter will review the terms of reference used throughout the work and will set a boundary around the area of examination. Chapter two will place musical improvisation within the context of human behaviour and in so doing will draw upon theoretical discourse from the fields of …

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Academic Feminism In Britain And The Usa 1980 And 1998: A Comparative Analysis, Rachel Torr Jan 2005

Academic Feminism In Britain And The Usa 1980 And 1998: A Comparative Analysis, Rachel Torr

Other Faculty of Arts, Humanities and Business Theses

Questions concerning the relationship between knowledge and other factors in the social world are among those that have been central to contemporary academic debates both within and outside of academic feminism. Linking into these debates, this study is guided by one central, underlying question; "What relationships exist between the changing perspectives, themes and contexts of academic feminism in Britain and the USA?" Four hypotheses form the framework for the project These hypotheses are informed by recent debates within feminist theory that appear to emphasise the dominance of poststructuralism in 1990s feminism and literature addressing the social shaping of knowledge. By …

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Writings, Readings And Not Writing: Poems, Prose Fiction And Essays, John Hall Jan 2005

Writings, Readings And Not Writing: Poems, Prose Fiction And Essays, John Hall

Other Faculty of Arts, Humanities and Business Theses

This submission of published work consists of a number of different modes of writing that interrelate as the concerns of a poet, essayist and teacher. There are twenty-seven separate publications, presented under six categories headings: (A) poems, including prose-poems, written for the page; (B) prose-fiction, represented through a single work; (C) visual poems; (D) enquiries into aspects of a general poetics, including questions about 'situatedness' or 'implicatedness', genres of discourse and their related modalities, poetics and grammar, and a poetics of reading; (E) critical and celebratory readings, mostly of contemporary poets and poems; (F) meditations on institutionalised divisions and modalities …

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A Biased Competition Computational Model Of Spatial And Object-Based Attention Mediating Active Visual Search, Linda Jane Lanyon Jan 2005

A Biased Competition Computational Model Of Spatial And Object-Based Attention Mediating Active Visual Search, Linda Jane Lanyon

School of Engineering, Computing and Mathematics Theses

A computational cognitive neuroscience approach was used to examine processes of visual attention in the human and monkey brain. The aim of the work was to produce a biologically plausible neurodynamical model of both spatial and object-based attention that accounted for observations in monkey visual areas V4, inferior temporal cortex (IT) and the lateral intraparietal area (LIP), and was able to produce search scan path behaviour similar to that observed in humans and monkeys. Of particular interest currently in the visual attention literature is the biased competition hypothesis (Desimone & Duncan. 1995). The model presented here is the first active …

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Consistency In Context‐Specific Measures Of Shyness And Boldness In Rainbow Trout, Oncorhynchus Mykiss, Alexander D.M. Wilson, E. D. Stevens Jan 2005

Consistency In Context‐Specific Measures Of Shyness And Boldness In Rainbow Trout, Oncorhynchus Mykiss, Alexander D.M. Wilson, E. D. Stevens

School of Biological and Marine Sciences

AbstractShyness and boldness has been considered a fundamental axis of human behavioural variation. At the extreme ends of this behavioural continuum subjects vary from being bold and assertive to shy and timid. Analogous patterns of individual variation have been noted in a number of species including fish. There has been debate on the nature of this continuum as to whether it depends on context. That is, whether it is domain‐general (as in humans), or context‐specific. The purpose of our study was to test if shyness and boldness depends on context in rainbow trout, Oncorhynchus mykiss and to this end we …

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Effects Of Ammonium Perchlorate On Thyroid Function In Developing Fathead Minnows, Pimephales Promelas, Hm Crane, Db Pickford, Th Hutchinson, Ja Brown Jan 2005

Effects Of Ammonium Perchlorate On Thyroid Function In Developing Fathead Minnows, Pimephales Promelas, Hm Crane, Db Pickford, Th Hutchinson, Ja Brown

School of Geography, Earth and Environmental Sciences

No abstract provided.

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Design Of An Automated Flow Injection-Chemiluminescence Instrument Incorporating A Miniature Photomultiplier Tube For Monitoring Picomolar Concentrations Of Iron In Seawater, Ar Bowie, Ep Achterberg, S Ussher, Pj Worsfold Jan 2005

Design Of An Automated Flow Injection-Chemiluminescence Instrument Incorporating A Miniature Photomultiplier Tube For Monitoring Picomolar Concentrations Of Iron In Seawater, Ar Bowie, Ep Achterberg, S Ussher, Pj Worsfold

School of Geography, Earth and Environmental Sciences

No abstract provided.

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Predicting Leadership And Performance In Uniformed Organisations Using The Five Factor Model Of Personality, Christopher John James Allender Jan 2005

Predicting Leadership And Performance In Uniformed Organisations Using The Five Factor Model Of Personality, Christopher John James Allender

School of Psychology Theses

Selection has been primarily focussed on the use of ability and aptitude measures as they have been shown to predict job performance in uniformed organisations. Personality assessment has largely been ignored as a possible contributor to improving predictions of performance. The emergence of the Five Factor Model as a framework for personality research, together with the development of the Trait Self Description Inventory (TSDI), has provided the opportunity to investigate how personality assessment might improve upon existing selection methods to predict performance in training. It was found that existing criterion measures did not fully reflect the core aims of the …

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Adiabatic Behavior Of Strongly Nonlinear Internal Solitary Waves In Slope-Shelf Areas, V Vlasenko, L Ostrovsky, K Hutter Jan 2005

Adiabatic Behavior Of Strongly Nonlinear Internal Solitary Waves In Slope-Shelf Areas, V Vlasenko, L Ostrovsky, K Hutter

School of Biological and Marine Sciences

No abstract provided.

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Generation Of Secondary Internal Waves By The Interaction Of An Internal Solitary Wave With An Underwater Bank, Vasiliy Vlasenko, Werner Alpers Jan 2005

Generation Of Secondary Internal Waves By The Interaction Of An Internal Solitary Wave With An Underwater Bank, Vasiliy Vlasenko, Werner Alpers

School of Biological and Marine Sciences

No abstract provided.

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Numerical Modelling Of Disintegration Of Basin-Scale Internal Waves In A Tank Filled With Stratified Water, N. Stashchuk, V. Vlasenko, K. Hutter Jan 2005

Numerical Modelling Of Disintegration Of Basin-Scale Internal Waves In A Tank Filled With Stratified Water, N. Stashchuk, V. Vlasenko, K. Hutter

School of Biological and Marine Sciences

We present the results of numerical experiments performed with the use of a fully non-linear non-hydrostatic numerical model to study the baroclinic response of a long narrow tank filled with stratified water to an initially tilted interface. Upon release, the system starts to oscillate with an eigen frequency corresponding to basin-scale baroclinic gravitational seiches. Field observations suggest that the disintegration of basin-scale internal waves into packets of solitary waves, shear instabilities, billows and spots of mixed water are important mechanisms for the transfer of energy within stratified lakes. Laboratory experiments performed by D. A. Horn, J. Imberger and G. N. …

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Construction And Validation Of A Bovine Innate Immune Microarray, L Donaldson, T Vuocolo, C Gray, Y Strandberg, Et Al Jan 2005

Construction And Validation Of A Bovine Innate Immune Microarray, L Donaldson, T Vuocolo, C Gray, Y Strandberg, Et Al

Peninsula Medical School

involved in the responses of cattle to disease challenges. This knowledge may allow the development of strategies that exploit these genes to enhance resistance to disease in an individual or animal population. Results The Bovine Innate Immune Microarray developed in this study consists of 1480 characterised genes identified by literature searches, 31 positive and negative control elements and 5376 cDNAs derived from subtracted and normalised libraries. The cDNA libraries were produced from 'challenged' bovine epithelial and leukocyte cells. The microarray was found to have a limit of detection of 1 pg/µg of total RNA and a mean slide-to-slide correlation co-efficient …

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The Correlation Grid: Analysis Of Synchronous Spiking In Multi-Dimensional Spike Train Data And Identification Of Feasible Connection Architectures, L Stuart, M Walter, R Borisyuk Jan 2005

The Correlation Grid: Analysis Of Synchronous Spiking In Multi-Dimensional Spike Train Data And Identification Of Feasible Connection Architectures, L Stuart, M Walter, R Borisyuk

School of Engineering, Computing and Mathematics

This paper presents a visualization technique specifically designed to support the analysis of synchronous firings in multiple, simultaneously recorded, spike trains. This technique, called the correlation grid, enables investigators to identify groups of spike trains, where each pair of spike trains has a high probability of generating spikes approximately simultaneously or within a constant time shift. Moreover, the correlation grid was developed to help solve the following reverse problem: identification of the connection architecture between spike train generating units, which may produce a spike train dataset similar to the one under analysis. To demonstrate the efficacy of this approach, results …

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Hcv-Specific Cellular Immune Responses In Subjects Exposed To But Uninfected By Hcv, M Metzner, A Houldsworth, Ag Demaine, E Kaminski, Me Cramp Jan 2005

Hcv-Specific Cellular Immune Responses In Subjects Exposed To But Uninfected By Hcv, M Metzner, A Houldsworth, Ag Demaine, E Kaminski, Me Cramp

Peninsula Medical School

No abstract provided.

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