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Power communications over the last kilometre
This thesis examines traditional methods of transmitting and receiving information over the last kilometre into homes and light industrial premises. As a direct result of the deregulation of electricity with the Electrical Deregulation Act of July 1989 [1] and the proliferation of large scale integration electronic devices such as microprocessors the need to transmit more data to and from such premises became urgent. The last kilometre problem of getting information to and from the customer’s premises to the node or data concentrator for connection to the available services, such as the internet, applies to any supplier from those that need to transfer large amounts of date such as on demand high definition television to those wishing to read utility meters remotely. Two competing techniques for transmitting small amounts of data at low data rates over the last kilometre between domestic and light commercial sites to the utility substation are investigated in this thesis. These techniques are narrow band VHF radio and low frequency power line carrier. A literature survey investigates the traditional methods of delivery information and the use of home networks and the latest research in power line carrier and broadband power line. The basis of radio propagation is presented including Maxwell’s equations. Two sets of trials are presented; the first set investigates a low frequency power line technology broadcast alarm system designed to inform residents living in higher risks areas around industrial sites such as oil refineries and chemical factories of important information and any alarm condition. The second set of trials, the radio trial, at 184 MHz, involved reading 2,500 domestic and light industrial electricity meters every 30 minutes during two week long periods. ConclusionBoth the radio meter reading system and low data rate power systems are viable in getting low data rate information to and from domestic and commercial properties. Both systems may be retrofitted quickly and cheaply depending on the data rates and amount of data to be transmitted. The radio meter system benefited from careful site surveys including monitoring of potential radio interference; the power line carrier system also benefited from site surveys and monitoring of line disturbance and line impedance
STUDIES ON MYXOZOAN PARASITES OF FRESHWATER FISH AND INVERTEBRATE HOSTS
A study of myxozoan parasites has been investigated in hosts from freshwater
environments in the UK. Over 17,000 oligochaetes, almost 5,000 juvenile cyprinids
representing 7 species and over 60 invertebrate species have been examined for the
presence of myxozoan parasites. In addition, studies on the lifecycle of
Tetracapsuloides bryosalmonae (the causative agent of salmonid proliferative kidney
disease, PKD) and of selected cyprinid myxozoans were conducted.
A total of 21 actinospore types in seven collective groups were isolated and
described from oligochaetes collected from seven different river systems in England
and Wales. Twelve of the actinospores isolated appear to be new to science.
Differences were noted in types of actinospores released at different sites and between
seasons. Most actinospores were released from oligochaetes in spring and summer
with prevalence of release ranging from 0.11% up to 5.83%. The most common
actinospores were members of the collective group Echinactinomyxon with seven
types identified, followed by the collective group Triactinomyxon, of which 6 types
were identified. Five actinospores types were each encountered only once during the
study.
In juvenile cyprinid fish, 14 identifiable species of myxozoans in the genera
Myxidium, Myxobolus and Sphaerospora plus three developmental stages were
detected by histological examination. The most common myxozoans in cyprinids
were Myxobolus pseudodispar and Myxobolus pfeifferi. Roach contained the most
number of myxozoan species. Only seven myxozoan species were found in chub, but
pathological responses and intensity of infections, particularly with M. pseudodispar,
M. pfeifferi and Myxobolus buckei were greater when compared to other cyprinids
examined. Juvenile cyprinids only appear to mount a pathological response to
myxozoans once sporogony is initiated and some of those responses were considered
severe enough to be detrimental to host survival.
Mathematical models were produced using parasite data and incorporating a
variety of data, including fish length, year class strength and environmental data to
attempt to demonstrate a population level effect of disease. Many of the models
developed clearly show that parasitism by Myxobolus spp. and Bucephalus
polymorphus in juvenile fish is strongly correlated with population success in selected
UK rivers.
Laboratory experiments to transmit Myxobolus spp., Myxidium spp. and
Sphaerospora spp. from selected cyprinid hosts to oligochaetes were unsuccessful.
The most likely explanation is that the genetic strain of Tubifex tubifex used in the
trials was not susceptible to infections by the myxospores selected.
Specific DNA primers for Tetracapsuloides bryosalmonae were used on
samples of over 60 invertebrate species collected from sites enzootic for PKD and on
all 21 actinospore types isolated during the current study. All PCR reactions were
negative for the presence of T. bryosalmonae DNA.
Naive rainbow trout exposed to T. bryosalmonae spores from naturally
infected bryozoans by bath challenge for 10 minutes developed PKD. Intraperitoneal
injection of spores failed to induce the disease. The favoured route of entry by the
parasite appears to be through mucous cells in the skin epithelium.The Centre for Environment, Fisheries and Aquaculture Science,
Weymouth, Dorse
Leeds: a geological background for planning and development : 1:10000 sheets SE23NW, NE, SE and SE33NW, NE, SW, SE: parts of 1:50000 geological sheets 69 (Bradford), 70 (Leeds), 77 (Huddersfield) and 78 (Wakefield)
This study, carried out between 1989 and 1991, was commissioned by the Department of the Environment and funded
jointly by the Department and the British Geological Survey. Its principal aim was to produce a synthesis of geological information relevant to the land-use planning for
development and redevelopment for a large part of the
Leeds district. This report is aimed at those involved in
planning and development. Much of the information is provided on a series of thematic maps, each of which concentrates on a specific aspect of the geology relevant to landuse. These are suitable for use in forward planning for development and conservation, and as a background to desk studies, prepared in advance of specific development proposals. However, they must not be used in place of results of adequate site investigations when development is being considered. In addition to the information contained in the report, sources of other more detailed data are indicated
Urinary biomarker discovery for type 2 diabetes
Diabetes mellitus is one of the most challenging health concerns of the 21st century. With at least 30% of the diabetic population remaining undiagnosed, the development of a diagnostic test, more convenient and reliable than those currently used, would be highly beneficial. Urine allows for non-invasive detection of biomarkers, and is a valuable source of biomarkers particularly for proteomic research. This project aimed at identifying and assessing potential urinary biomarkers for the diagnosis of Type 2 diabetes using proteomic techniques.
After determining an efficient method to desalt and concentrate urine samples, 2-DE was performed on a small set of diabetic and control samples. Comparison of electrophoretic patterns and identification of proteins using LC- MS/MS allowed the selection of several potential biomarkers. The two most prominent markers, transferrin and kininogen, were then assessed on a larger set of samples using immunodetection methods.
Urinary transferrin excretion was measured using a commercial ELISA kit in 56 Type 2 diabetic and matched control samples. As observed on 2-DE patterns, transferrin excretion was significantly increased in Type 2 diabetic patients, although only in microalbuminuric patients compared to both diabetic normoalbuminuric (mean difference = 183.7 μg/mmol; p = 0.005) and control normoalbuminuric (mean difference = 171.1 μg/mmol; p = 0.007) patients.
SDS-PAGE western blotting allowed the semi-quantification of several kininogen isoforms/fragments in 44 Type 2 diabetic and matched control samples. Significant under-expression of the kininogen isoforms/fragments located at 50-65 kDa, as observed in the diabetic 2-DE patterns, was not confirmed. However, variation in intensity ratio for the main kininogen bands (at 50-65 kDa and 100-120 kDa) was close to significance between the diabetic normoalbuminuric and control normoalbuminuric patients, suggesting that the several kininogen isoforms/fragments may be excreted in altered proportions in Type 2 diabetes.
This preliminary study, although limited by the small population size and the lack of thorough clinical diagnosis in the recruitment of patients, confirmed the usefulness of proteomics as a first step in urinary biomarker discovery. Results suggested that both transferrin and kininogen may be biomarkers of interest for the development of better diagnostic tests for Type 2 diabetes, although further investigations are required
Urban regime theory in critical perspective : a comparative study of public-private partnerships in UK local governance.
SIGLEAvailable from British Library Document Supply Centre-DSC:DXN037027 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Lateral systems for tall buildings
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.Includes bibliographical references.The advances in three-dimensional structural analysis and computing resources have allowed the efficient and safe design of increasingly taller structures. These structures are the consequence of increasing urban densification and economic viability. The modern skyscraper has and will thus continue to feature prominently in the landscape of urban cities. The trend towards progressively taller structures has demanded a shift from the traditional strength based design approach of buildings to a focus on constraining the overall motion of the structure. Structural engineers have responded to this challenge of lateral control with a myriad of systems that achieve motion control while adhering to the overall architectural vision. An investigation was carried out to understand the behavior of the different lateral systems employed in today's skyscrapers. The investigation examined the structural behavior of the traditional moment frame, the braced frame, the braced frame with outriggers and finally the tubular structure. The advantages and disadvantages of all schemes were explored from both an architectural and structural efficiency standpoint. Prior to the computer modeling of each lateral system, each scheme was understood from an analytical standpoint to both verify computer results and to illustrate the importance of hand calculations. The study repeatedly illustrated that motion was the governing condition and this led to the proposal of an approach for the design of braced frames.by Kermin Chok.M.Eng
Problem structuring methods for development: A conceptual clarification with an application to participative health services planning in Mexico.
Participatory development planning methods (PDPMs) have been developed within the 'people-centred' approach to development. Independently, problem structuring methods (PSMs) have been developed within operational research (OR). Both families of methods claim to assist empowerment and participation. Nevertheless, these concepts are used in ill-defined or even contradictory ways. The aim of this research is to explore to what extent claims made that PSMs can assist in development in the Third World are justified. The hypothesis developed and adopted during this research is that the analytic assistance provided by PSMs can be expected to contribute to a process of empowerment of the disadvantaged principally through improving participants' understanding of their problematic situation, and through providing structure to this understanding. PSMs generate this effect through improving the quality of dialogue between participants. Other more indirect expected effects are also identified. In combination, these effects should tend to impact positively on commitments to a course of action, and on longer term increases in self-power. In order to articulate this hypothesis it has been necessary to conduct some conceptual clarification to achieve a clear meaning for the terms "power", "self-power", "participation", "empowerment", and "spaces for dialogue". Using this as a base, a conceptual model of empowerment as a process has been developed, which identifies the factors, pre-requisites and processes involved in disadvantaged social actors' ability to maintain or augment their self-power. This model provides the bases for identifying the possible effects of PSMs, and for evaluating their effectiveness. To explore both our hypothesis and the adequacy of the conceptual model, a case study of the application of one PSM - the Strategic Choice Approach (SCA) - in a grassroots situation was carried out. This involved engagement in and observation of ongoing developmental activity of the Community Health Committee in a small town in Mexico. Reasonably clear and positive effects from the application of SCA were found in several model elements, consistent with the hypothesis. The effects in other elements were more ambiguous. Overall the results of the case study are encouraging; however, as they result from the application of a particular PSM, extrapolation to more general conclusions about the potential of PSMs to empower disadvantaged social actors should be made with caution. The case experience also was generally supportive of the conceptual model of empowerment, in that observed activities and processes could be interpreted unproblematically within the model's framework. The model offers a vehicle for further research aimed at confirming and enriching its structure
Molecular modelling and experimental studies of the interactions between biomolecules and nanostructured inorganic materials
In this study the interactions of biomacromolecules with different inorganic nanostructured materials were investigated using experimental and theoretical approaches. A deeper understanding on the fundamental steps involved for such interactions is very important for the fields of nanotechnology, medicine and biotechnology. In nanotechnology biomolecules like DNA have often been considered as templates for the scaffolding of nanoparticles. TEM observations of DNA molecules with Au55 cluster indicated the formation of equidistant gold nanowires. Interestingly the nanowires were composed of such dimensions that indicated that the Au55 cluster initially used was reduced to the size of a cluster with 13 gold atoms. In order to understand the formation of gold nanowires, various molecular modelling techniques were employed. Based on molecular mechanics simulations, it was found that Au55 cluster energetically prefers to interact with the major groove of B-DNA whereas Au13 prefers to associate with the major grooves of A-DNA. It is not clear how the reduction of Au55 to Au13 occurs however it is assumed that it is influenced by the dramatic alterations occurring in the groove geometry during B-DNA to A-DNA transition. The formation of gold nanowires is determined by the equidistant decoration of Au13 clusters around the major grooves of A-DNA. Molecular dynamics simulations indicated that the aggregation of such DNA-gold complexes leads to the formation of nanowires which are separated from each other almost 0.5 nm.
The ability of Au55 to interact with the major grooves of B-DNA led to further investigations on the potential of this gold cluster as an anticancer drug. Gold-based compounds have not been studied as extensively as other metal-based drugs like platinum derivatives which have been employed as chemotherapeutic agents for many years in medical oncology. A variety of human cancer and healthy cell lines have been employed for investigating sensitivity towards Au55 and cisplatin. In vitro cytotoxicity assays performed by a colourimetric-based method (MTT) have indicated that generally Au55 is more toxic and efficient than cisplatin. Especially the cisplatin resistant metastatic melanoma cell lines exhibited the highest sensitivity towards Au55. Apoptotic or necrotic death influenced by Au55 was investigated by performing a fluorometric assay which measures the induction of the apoptotic proteins caspases 3 and 7. The effect of Au55 was different among the five cell lines investigated. In the case of the osteosarcoma cell line U-2OS induction of caspases 3 and 7 in the presence either of Au55 or cisplatin was observed indicating apoptosis being triggered. In the other four different cell lines the induction of caspases either in the presence of Au55 or cisplatin was similar to the controls. This indicates that these cells could be dying either by necrosis, or apoptosis is induced through a caspase-independent pathway. Further information on the cellular localisation and possible target has been investigated by measuring the distribution of radioactive gold cluster in various cellular fractions of the BLM cell line. It has been found that slightly higher amount of Au55 was located in the chromosomal DNA rather than in the cytoplasmic fraction. The Au55 was strongly bound to the chromosomal DNA with a very small fraction of it being present in the nuclear proteins. This has indicated that DNA is one of the main cellular targets however it is not certain whether such an interaction is directly related to the cytotoxic effect of Au55. The gold cluster could possibly damage the chromosomal DNA in the presence of H2O2 as indicated by the conversion of supercoiled plasmid DNA into open-circular form by agarose gel electrophoresis. Molecular docking simulations have shown the energetic preference of this agent for AATT sequences which is different to the GG and AG preference of cisplatin. Finally protein-gold cluster interactions could also play an important role on the cytotoxic effect of Au55. In vitro cytotoxicity assays in the presence of albumin have shown an increase in the IC50 values indicating a sequestering effect of albumin protein. Molecular docking simulations suggest the interaction of Au55 with specific cystein residues of human albumin.
Nanostructured inorganic materials have been considered very important in the field of biotechnology with major applications aiming towards the immobilisation or purification of biomolecules such as proteins and amino acids. In this study the interactions of three different amino acids with a zeolite structure have been investigated using molecular modelling. MD simulations have been performed in the presence of water molecules with Phe, Lys and Glu being placed around the structure of zeolite beta. The simulations have indicated that amino acids energetically prefer to interact with the surface of the zeolite-beta rather being placed inside the pores or in the bulk. MD simulations clearly indicate the preference of Phe to adsorb through the formation of hydrogen bonds with the O atoms of the zeolite structure. The amino acids Lys and Glu have indicated a lower preference as the formation of fewer hydrogen bonds with the zeolite surface has been exhibited. This is in aggreement with experimental studies reported in the literature. Nevertheless MD simulations have not been able to distinguish any differences on the adsorption behavior of Glu and Lys
From the margins to the centre and back : trajectories of regeneration in two marginal English coalfields
Regeneration is a ubiquitous feature of the contemporary British state. Research, despite devoting much time to exploration of outcomes and effects, so far has neglected the mechanisms of the process itself. This thesis addresses this by charting developments in two marginal English coalfields over a period of 25 years. The coalfields provide a convenient site for the investigation of regeneration as they offer multiple critical sites and exhibit in particularly acute forms the effects of changing relationships between the central and the local state and thus exemplify the wider relationships between the state, the market and the locality. The choice of the coalfields in North West Leicestershire and East Kent as case studies was informed by their position in the coal mining industry at the beginning of the period of its major restructuring, the then recent evaluation on the recovery of the coalfields (Beatty et al., 2005) and their location in relation to national "identity" projects (e.g. the National Forest). The thesis employs the extended case method as outlined by Burawoy. On the basis of extensive archive research of local government documentation, semi-structured interviews with policy makers and civil society actors and a 6-month observation period in the Kent coalfield an understanding of regeneration as a multi-dimensional social process is delineated. Through the use of Bourdieu's notion of the field and different forms of capital (1984, 1986) the thesis offers an examination of regeneration as a sequence of contests in the economic, social and symbolic repositioning of localities in the social space. The combination of Bourdieu's and Burawoy's concepts allows exploring the systematicity of the regeneration process through the lens of place. It thus provides a framework for the analysis the spatially and temporally contingent outcomes of (1) processes of legitimisation, (2) the production of specific sets of social relations and (3) the operation of symbolic power in the context of different regeneration regimes.EThOS - Electronic Theses Online ServiceGBUnited Kingdo