18 resultados para obligation to provide information
em Aston University Research Archive
A study of load support and other criteria appropriate to the selection of industrial conveyor belts
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A study of conveying practice demonstrates that belt conveyors provide a versatile and. much-used method of transporting bulk materials, but a review of belting manufacturers' design procedures shows that belt design and selection rules are often based on experience with all-cotton belts no longer in common use, and are net completely relevant to modern synthetic constructions. In particular, provision of the property "load support", which was not critical with cotton belts, is shown to determine the outcome of most belt selection exercises and lead to gross over specification of other design properties in many cases. The results of an original experimental investigation into this property, carried out to determine the belt and conveyor parameters that affect it, how the major role that belt stiffness plays in its provision; the basis for a belt stiffness test relevant to service conditions is given. A proposal for a more rational method of specifying load support data results from the work, but correlation of the test results with service performance is necessary before the absolute toad support capability required from a belt for given working conditions can be quantified. A study to attain this correlation is the major proposal for future work resulting from the present investigation, but a full review of the literature on conveyor design and a study of present practice within the belting industry demonstrate other, less critical, factors that could profitably be investigated. It is suggested that the most suitable method of studying these would be a rational data collection system to provide information on various facets of belt service behaviour; a basis for such a system is proposed. In addition to the work above, proposals for simplifying the present belt selection methods are made and a strain transducer suitable for use in future experimental investigations is developed.
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The surface epithelial cells of the stomach represent a major component of the gastric barrier. A cell culture model of the gastric epithelial cell surface would prove useful for biopharmaceutical screening of new chemical entities and dosage forms. Primary cultures of guinea pig gastric mucous epithelial cells were grown on filter inserts (Transwells®) for 3 days. Tight-junction formation, assessed by transepithelial electrical resistance (TEER) and permeability of mannitol and fluorescein, was enhanced when collagen IV rather than collagen I was used to coat the polycarbonate filter. TEER for cells grown on collagen IV was close to that obtained with intact guinea pig gastric epithelium in vitro. Differentiation was assessed by incorporation of [ 3H]glucosamine into glycoprotein and by activity of NADPH oxidase, which produces superoxide. Both of these measures were greater for cells grown on filters coated with collagen I than for cells grown on plastic culture plates, but no major difference was found between cells grown on collagens I and IV. The proportion of cells, which stained positively for mucin with periodic acid Schiff reagent, was greater than 95% for all culture conditions. Monolayers grown on membranes coated with collagen IV exhibited apically polarized secretion of mucin and superoxide, and were resistant to acidification of the apical medium to pH 3.0 for 30 min. A screen of nonsteroidal anti-inflammatory drugs revealed a novel effect of diclofenac and niflumic acid in reversibly reducing permeability by the paracellular route. In conclusion, the mucous cell preparation grown on collagen IV represents a good model of the gastric surface epithelium suitable for screening procedures. © 2005 The Society for Biomolecular Screening.
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High street optometric practices are for-profit businesses. They mostly provide sight testing and eye examination services and sell optical products, such as spectacles and contact lenses. The sight testing services are often sold at a vastly reduced price and profits are generated primarily through high margin spectacle sales, in a loss leading strategy. Published literature highlights weaknesses in this strategy as it forms a barrier to widening the scope of services provided within optometric practices. This includes specialist non-refraction based services, such as shared care. In addition this business strategy discourages investment in advanced diagnostic equipment and higher professional qualifications. The aim of this thesis was to develop a greater understanding of the traditional loss-leading strategy. The thesis also aimed to assess the plausibility of alternative business models to support the development of specialist non-refraction services within high street optometric practice. This research was based on a single independent optometric practice that specialises in advanced retinal imaging and offers a broad range of shared care services. Specialist non-refraction based services were found to be poor generators of spectacle sales likely due to patient needs and presenting concerns. Alternative business strategies to support these services included charging more realistic professional fees via cost-based pricing and monthly payment plans. These strategies enabled specialist services to be more self-sustainable with less reliance on cross-subsidy from spectacle sales. Furthermore, improving operational efficiency can increase stand-alone profits for specialist services.Practice managers may be reluctant to increase professional fees due to market pressures and confidence. However, this thesis found that patients were accepting of increased professional fees. Practice managers can implement alternative business models to enhance eye care provision in high street optometric practices. These alternative business models also improve revenues and profits generated via clinical services and improve patient loyalty.
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Aims: To explore newly diagnosed Type 2 diabetes patients' views about Scottish diabetes services at a time when these services are undergoing a major reorganization. To provide recommendations to maximize opportunities brought by the devolvement of services from secondary to primary healthcare settings. Methods: Qualitative panel study with 40 patients newly diagnosed with Type 2 diabetes, recruited from hospital clinics and general practices in Lothian, Scotland. Patients were interviewed three times over 1 year. The study was informed by grounded theory, which involves concurrent data collection and analysis. Results: Patients were generally satisfied with diabetes services irrespective of the types of care received. Most wanted their future care/review to be based in general practice for reasons of convenience and accessibility, although they dis-liked it when appointments were scheduled for different days. Many said they lacked the knowledge/confidence to know how to manage their diabetes in particular situations, and needed access to healthcare professionals who could answer their questions promptly. Patients expressed a need for primary care professionals who had diabetes expertise, but who had more time and were more accessible than general practitioners. Patients who had encountered practice lead nurses for diabetes spoke particularly positively of these professionals. Conclusions: Nurses with diabetes training are particularly well placed to provide information and support to patients in primary care. Ideally, practices should run 'one-stop' diabetes clinics to provide structured care, with easily accessible dietetics, podiatry and retinopathy screening. Newly diagnosed patients may benefit from being made more aware of specific services provided by charitable organizations such as Diabetes UK. © 2005 Diabetes UK.
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Conventional feed forward Neural Networks have used the sum-of-squares cost function for training. A new cost function is presented here with a description length interpretation based on Rissanen's Minimum Description Length principle. It is a heuristic that has a rough interpretation as the number of data points fit by the model. Not concerned with finding optimal descriptions, the cost function prefers to form minimum descriptions in a naive way for computational convenience. The cost function is called the Naive Description Length cost function. Finding minimum description models will be shown to be closely related to the identification of clusters in the data. As a consequence the minimum of this cost function approximates the most probable mode of the data rather than the sum-of-squares cost function that approximates the mean. The new cost function is shown to provide information about the structure of the data. This is done by inspecting the dependence of the error to the amount of regularisation. This structure provides a method of selecting regularisation parameters as an alternative or supplement to Bayesian methods. The new cost function is tested on a number of multi-valued problems such as a simple inverse kinematics problem. It is also tested on a number of classification and regression problems. The mode-seeking property of this cost function is shown to improve prediction in time series problems. Description length principles are used in a similar fashion to derive a regulariser to control network complexity.
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The investigations described in this thesis concern the molecular interactions between polar solute molecules and various aromatic compounds in solution. Three different physical methods were employed. Nuclear magnetic resonance (n.m.r.) spectroscopy was used to determine the nature and strength of the interactions and the geometry of the transient complexes formed. Cryoscopic studies were used to provide information on the stoichiometry of the complexes. Dielectric constant studies were conducted in an attempt to confirm and supplement the spectroscopic investigations. The systems studied were those between nitromethane, chloroform, acetonitrile (solutes) and various methyl substituted benzenes. In the n.m.r. work the dependence of the solute chemical shift upon the compositions of the solutions was determined. From this the equilibrium quotients (K) for the formation of each complex and the shift induced in the solute proton by the aromatic in the complex were evaluated. The thermodynamic parameters for the interactions were obtained from the determination of K at several temperatures. The stoichiometries of the complexes obtained from cryoscopic studies were found to agree with those deduced from spectroscopic investigations. For most systems it is suggested that only one type of complex, of 1:1 stiochiometry, predominates except that for the acetonitrile-benzene system a 1:2 complex is formed. Two sets of dielectric studies were conducted, the first to show that the nature of the interaction is dipole-induced dipole and the second to calculate K. The equilibrium quotients obtained from spectroscopic and dielectric studies are compared. Time-averaged geometries of the complexes are proposed. The orientation of solute, with respect to the aromatic for the 1:1 complexes, appears to be the one in which the solute lies symmetrically about the aromatic six-fold axis whereas for the 1:2 complex, a sandwich structure is proposed. It is suggested that the complexes are formed through a dipole-induced dipole interaction and steric factors play some part in the complex formation.
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This thesis reports on the development of a technique to evaluate hydraulic conductivities in a soil (Snowcal) subject to freezing conditions. The technique draws on three distinctly different disciplines, Nuclear Physics, Soil Physics and Remote Sensing to provide a non-destructive and reliable evaluation of hydraulic conductivity throughout a freezing test. Thermal neutron radiography is used to provide information on local water/ice contents at anytime throughout the test. The experimental test rig is designed so that the soil matrix can be radiated by a neutron beam, from a nuclear reactor, to obtain radiographs. The radiographs can then be interpreted, following a process of remote sensing image enhancement, to yield information on relative water/ice contents. Interpretation of the radiographs is accommodated using image analysis equipment capable of distinguishing between 256 shades of grey. Remote sensing image enhancing techniques are then employed to develop false colour images which show the movement of water and development of ice lenses in the soil. Instrumentation is incorporated in the soil in the form of psychrometer/thermocouples, to record water potential, electrical resistance probes to enable ice and water to be differentiated on the radiographs and thermocouples to record the temperature gradient. Water content determinations are made from the enhanced images and plotted against potential measurements to provide the moisture characteristic for the soil. With relevant mathematical theory pore water distributions are obtained and combined with water content data to give hydraulic conductivities. The values for hydraulic conductivity in the saturated soil and at the frozen fringe are compared with established values for silts and silty-sands. The values are in general agreement and, with refinement, this non-destructive technique could afford useful information on a whole range of soils. The technique is of value over other methods because ice lenses are actually seen forming in the soil, supporting the accepted theories of frost action. There are economic and experimental restraints to the work which are associated with the use of a nuclear facility, however, the technique is versatile and has been applied to the study of moisture transfer in porous building materials and could be further developed into other research areas.
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The study examines the job satisfaction of supervisors and managers in four organisations over time. It also considers the importance which they attached to different facets of their job. The major objectives were: To examine the constituent dimensions of job satisfaction at intervals over one year. To examine reasons for change inthe level of job satisfaction at intervals over one year. To provide information on job satisfaction for those concerned with job satisfaction policies. The sample consisted of one hundred and eight people. Each was interviewed on at least three occasions over the course of a year. Interviews took place at predetermined time intervals. The study shows that job satisfaction is dynamic over a relatively short period of time. The ratings which supervisors and managers gave to aspects of their job did not, however, all change by equal amounts or in the same direction. Changes in job satisfaction were associated with events experienced but it was the meaning of those events to correspondents which appeared to be particularly important. People tended to adopt a localised frame of reference when considering their work situation. Certain job variables, such as variety, were consistently and positively correlated with job satisfaction. With some other variables, the relationship varied across time. Frequently, age and job level moderated the association between independent variables and job satisfaction. Links were found between the quality of life and job satisfaction. There was a consistent positive association between job satisfaction and life satisfaction. However, the job was rarely considered to be the main factor contributing to a person's quality of life. The research highlights the difficulties and desirability of introducing standardised job satisfaction policies in the light of individual differences. In addition, it demonstrates that merely correlating variables with job satisfaction at one point in time may conceal complex relationships and meanings. A new measure of job satisfaction - whereby facets are assessed and rated relative to each other was also developed as part of this study.
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The issues involved in planning for pedal cyclists are examined with reference to the West Midlands County. Working with a local cycling campaign group, the researcher uses action research methods to investigate and influence the campaign. Development of cycle planning is traced through the literature, focusing on bicycle ownership, bicycle use and cycling policy. UK practice is contrasted with the integrated approach of other countries. An extensive bibliography is provided. Local authority cycle planning through the TPP process is systematically assessed over three years. This provides a context for the information regarding cycling in the West Midlands. Existing data is presented from the 1981 Census and local police road accident and bicycle theft records. The developing relationship between the local authority and the cycle campaign group is narrated in detail, explaining the problems that can beset efforts to improve conditions for cyclists. The researcher was closely involved in this interaction, particularly with policy and a major public inquiry. A survey of the Cycle Campaign Network indicates that the local group was not atypical. To provide information relevant to the local campaign and for effective local planning, a survey of 3,500 West Midlands residents was conducted using a novel combination of questionnaires and interviews. It shows that 1) Bicycle ownership and use is considerably higher than indicated by the 1978/9 National Travel Survey 2) Cycling is most import to certain disadvantaged sections of the community, particularly the young, those without access to a car and in the lower SEGs. The broader issues of transport policy are discussed, concluding that cycling is regarded as a marginal activity and that changes in general transport policy, land use planning and fiscal arrangements are necessary conditions for cycle planning to succeed. An integrated package of cycling measures involving engineering, education, enforcement and encouragement is also required. Recommendations are made concerning central government, local authorities and cycle campaign groups. Subjects for further research are identified.
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The diagnosis of ocular disease is increasingly important in optometric practice and there is a need for cost effective point of care assays to assist in that. Although tears are a potentially valuable source of diagnostic information difficulties associated with sample collection and limited sample size together with sample storage and transport have proved major limitations. Progressive developments in electronics and fibre optics together with innovation in sensing technology mean that the construction of inexpensive point of care fibre optic sensing devices is now possible. Tear electrolytes are an obvious family of target analytes, not least to complement the availability of devices that make the routine measurement of tear osmolarity possible in the clinic. In this paper we describe the design, fabrication and calibration of a fibre-optic based electrolyte sensor for the quantification of potassium in tears using the ex vivo contact lens as the sample source. The technology is generic and the same principles can be used in the development of calcium and magnesium sensors. An important objective of this sensor technology development is to provide information at the point of routine optometric examination, which would provide supportive evidence of tear abnormality.
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In an ever-changing higher education (HE) environment, institutions are seeing the involvement of parents in students' education increasing. This may partly be due to tuition fees and the introduction of deferred variable tuition fees ("top-up fees") from 2006, and also because of the increased number of students choosing to remain in the family home for the duration of their studies. Many students see their families as the most important source of motivation and advice right through from school age to when they make decisions about HE. In the light of this increase in involvement, institutions need to provide information about, and access to, university to ensure that families are fully prepared and able to support their children throughout the university experience. In recognition of the vital role parents play, the Involving the Family project focuses on parents or key family members from groups currently under-represented in HE in order to increase their awareness and understanding of HE. This article evaluates research undertaken to investigate the views, perceptions and key concerns held by minority ethnic parents with regards to their children and participation in HE. The article then details how these results were utilised in the development of the Involving the Family project.
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The editorial section of the special issue of Production Planning & Control discusses contemporary approaches and scope for further research into the management of supply chain integration. Supply chain integration (SCI) is one of the major challenges in enhancing supply chain performance. Building and sustaining competitive advantage requires strategic collaboration between supply chain partners and synchronized management of intra- and inter-organizational practices and processes. The special issue attempts to address some of the fundamental SCI questions, which include but are not limited to the fields of organizational collaboration, information technology (IT) use, and risk and vulnerability management. The editorial first reviews a few key articles on SCI to provide information about the existing state of knowledge on SCI along with scope for further research.
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Protein oxidation is increasingly recognised as an important modulator of biochemical pathways controlling both physiological and pathological processes. While much attention has focused on cysteine modifications in reversible redox signalling, there is increasing evidence that other protein residues are oxidised in vivo with impact on cellular homeostasis and redox signalling pathways. A notable example is tyrosine, which can undergo a number of oxidative post-translational modifications to form 3-hydroxy-tyrosine, tyrosine crosslinks, 3-nitrotyrosine and halogenated tyrosine, with different effects on cellular functions. Tyrosine oxidation has been studied extensively in vitro, and this has generated detailed information about the molecular mechanisms that may occur in vivo. An important aspect of studying tyrosine oxidation both in vitro and in biological systems is the ability to monitor the formation of oxidised derivatives, which depends on a variety of analytical techniques. While antibody-dependent techniques such as ELISAs are commonly used, these have limitations, and more specific assays based on spectroscopic or spectrometric techniques are required to provide information on the exact residues modified and the nature of the modification. These approaches have helped understanding of the consequences of tyrosine oxidation in biological systems, especially its effects on cell signalling and cell dysfunction, linking to roles in disease. There is mounting evidence that tyrosine oxidation processes are important in vivo and can contribute to cellular pathology.