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A Digital Filter/Estimator For The Control Of Large Ships In Confined Waters, Michael John Dove Jan 1984

A Digital Filter/Estimator For The Control Of Large Ships In Confined Waters, Michael John Dove

Other Faculty of Science and Engineering Theses

Aeronautical and marine casualty statistics indicate that the human being, when under stress or at times of peak load, can be a poor co-ordinator of the information available to him, particularly when that information is from a number of different source:, as is often the case in modern ships. Integration and co-ordination of information and its useful application in a closed loop feedback system can reduce the probability of accident as has already been demonstrated in the case of automatic landing systems for aircraft. This thesis describes the development of a digital filter/estimator for use in conjunction with an optimal …

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The Importance Of Marital Status For Women's Lives, Anthea Duquemin Jan 1984

The Importance Of Marital Status For Women's Lives, Anthea Duquemin

Other Faculty of Arts, Humanities and Business Theses

This thesis aims to investigate the ways in which women's marital status influences various aspects of their lives. With the growing sociological interest in women many statements have been made and theories put forward, the majority of which assume women to be wives and mothers. The intention of this thesis is to examine whether such theories are relevant to all women, irrespective of their marital status and merely because of their gender, or only to those women who have husbands of their own. Much emphasis has been placed on context in this study, for individuals' lives can only clearly be …

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Patterns Of Occupational Mobility Amongst Men And Women In Scotland: 1930-1970, Anthony D. Chapman Jan 1984

Patterns Of Occupational Mobility Amongst Men And Women In Scotland: 1930-1970, Anthony D. Chapman

Other Faculty of Arts, Humanities and Business Theses

Researchers and writers on occupational and social mobility have attracted a good deal of criticism over the past ten years because they have not included women in their analyses. Accusations of 'intellectual' sexism have provoked different responses from researchers in this field; some have tried to remedy the empirical and theoretical deficiencies of earlier research, whilst others refute the validity of such attacks at a theoretical level. In this thesis it is argued that the exclusion of women from mobility analysis is unacceptable at a theoretical level. Those researchers who have not considered the case of women's mobility, it is …

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The Germination Requirements Of Naturally Buried Seeds With Particular Reference To Fluctuating Temperatures, Jean Carol Whatley Jan 1984

The Germination Requirements Of Naturally Buried Seeds With Particular Reference To Fluctuating Temperatures, Jean Carol Whatley

School of Biological and Marine Sciences Theses

An apparatus is described which enables a layer of soil, containing naturally buried seeds, to be subjected to controlled temperature fluctuations over the range 5 C to 30 C, in the presence or absence of light. Results obtained from the use of this apparatus are presented for fourteen species, all common constituents of the buried seed bank and nearly all weeds of arable land or pasture. At least partial inhibition of germination by darkness is found in all fourteen species and stimulation of germination by temperature fluctuations in all but one. In several species strong inhibition by certain constant temperatures …

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Hepatic Microsporidiosis Of Juvenile Grey Mullet, Chelon Labrosus, With Particular Reference To Parasite Development And Transmission, James R. Ralphs Jan 1984

Hepatic Microsporidiosis Of Juvenile Grey Mullet, Chelon Labrosus, With Particular Reference To Parasite Development And Transmission, James R. Ralphs

School of Biological and Marine Sciences Theses

Microgemma hepaticus gen.n.sp.n. is described from the liver of juvenile mullet, Chelon labrosus. Development occurs within xenomas, of diameter 500 µm. These have microvillar surfaces, encircling bands of mitochondria and a reticulate nucleus with many nucleoli. Meronts are plasmodial, divide by plasmotomy and are enclosed within host membranes. Sporonts are free in the cytoplasm and divide by multiple exogenous budding. In sporogenesis the polar sac is formed from golgi vesicles, the manubrium form a dense golgi body and the coiled polar filament form a spiral cisterna linked with the perinuclear membrane system and golgi reticulum. This was also implicated in …

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An Analysis Of The Role Of Linkages In Peripheral Area Development: The Case Of Devon And Cornwall, Stephen Mark Dobson Jan 1984

An Analysis Of The Role Of Linkages In Peripheral Area Development: The Case Of Devon And Cornwall, Stephen Mark Dobson

Plymouth Business School Theses

The thesis examines the significance for economic development in Devon and Cornwall of the material and business service linkages of manufacturing establishments. Industrial linkages can play a key role in promoting regional growth, whilst the nature of the relationship between linkages and economic growth is further understood by focusing attention at establishment level. Thus, using data drawn from a survey of 366 manufacturing plants in Devon and Cornwall, the thesis considers the extent to which differing types of establishment possess local suppliers and markets. The primary focus is the importance of key variables as an indicator for variations in linkage …

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Impact Pressures Of Sea Waves, Alexander L. Rossi Jan 1984

Impact Pressures Of Sea Waves, Alexander L. Rossi

School of Engineering, Computing and Mathematics Theses

Following previous work (by P. Blackmore, 1982, at Plymouth Polytechnic) more detailed pressure measurements were taken at Ilfracombe, North Devon and at a new site, Bovisand, near Plymouth. In both cases a beach array of transducers was used to enable a determination of wave characteristics for correlation with impact pressures. At both sites, the tidal variations were exploited to obtain depth dependent parameters such as wave steepness and their effect on impact pressure magnitude and variation. The bulk of the readings come from Ilfracombe, as storm damage brought a temporary halt to work at Bovisand. The wave profile can be …

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Investigation Of Ocular Artefacts In The Human Eeg And Their Removal By A Microprocessor-Based Instrument, Emmanuel Ifeachor Jan 1984

Investigation Of Ocular Artefacts In The Human Eeg And Their Removal By A Microprocessor-Based Instrument, Emmanuel Ifeachor

School of Engineering, Computing and Mathematics Theses

The Electroencephalogram (EEG) is widely used in clinical and psychological situations, but it is often seriously obscured by ocular artefacts (OAs) resulting from movements in the ocular system (eyeball, eyelids etc). 'The work described in this thesis is concerned with the problems of OAs in the human EEG, their removal both off-line and on-line, and the design and development of an on-line OA removal system, together with a critical review of the literature on the subject. The work of Jervis and his co-workers was extended to further study OAs, to obtain improved measures of the effectiveness of OA removal, and …

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Some Cryptographic Techniques For Secure Data Communication, Vijayaraghavan Varadharajan Jan 1984

Some Cryptographic Techniques For Secure Data Communication, Vijayaraghavan Varadharajan

School of Engineering, Computing and Mathematics Theses

This thesis investigates conventional and public key cryptographic techniques for secure data communication. Block and stream cipher methods to provide secure communication over an insecure channel are discussed with particular reference to the Data Encryption Standard (DES) algorithm. A microprocessor based data encryption interface unit has been designed and constructed using the DES to provide both communication and file security. Several chaining techniques using the system have also been investigated enabling a study of their error characteristics, speed of operation, level of security and their ability to overcome difficulties due to data redundancy and structure. A statistical analysis of the …

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Visual And Verbal Processing In Reasoning, Philip Graham Brooks Jan 1984

Visual And Verbal Processing In Reasoning, Philip Graham Brooks

School of Psychology Theses

This programme of research, involving seven experiments, investigates Evans' (1980a; 1980b) revised version of the Dual Process theory of reasoning (Wason and Evans, 1975). A Type 2 process is characterised as verbal-rational and a Type I process as non-verbal and non-logical. Evans links the processes to two statistical components of observed reasoning performance. The Type I process reflects non-logical response biases and the Type 2 process reflects attention to the logical nature of the task. Six experiments employ a concurrent articulation (with or without a short-term memory load) methodology devised by Baddeley and Hitch (1974) for investigating their Working Memory …

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The Removal Of Arsenic From Aquatic Systems By Iron Oxyhydroxides, John Graham Marsh Jan 1983

The Removal Of Arsenic From Aquatic Systems By Iron Oxyhydroxides, John Graham Marsh

School of Biological and Marine Sciences Theses

Surveys of dissolved Fe, Mn and As in the River Tamar, Devon, indicated general removal from the water column at low salinities. Manganese and As showed evidence of remobilisation at higher salinities. Total and non-detrital sediment extracts confirmed a remobilisation chemistry for Mn and non-detrital As, and a redox couple between Mn and As was considered. Spatial-temporal analysis of sediment data indicated both physical and chemical processes were involved in the estuarine transport of these elements. Studies of synthetic and natural Fe precipitates indicated that speciation of the Fe source and temperature of formation influenced the surface area and nature …

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The Removal And Remobilisation Of Heavy Metals During Estuarine Mixing, David Roger Ackroyd Jan 1983

The Removal And Remobilisation Of Heavy Metals During Estuarine Mixing, David Roger Ackroyd

School of Biological and Marine Sciences Theses

Elemental analyses have been made of dissolved, suspended particulate and sedimentary Cu, Mn, Zn following axial surveys of the Tamar Estuary. Continuous monitoring of the estuarine master variables was made during each survey. Selective digestion methods were applied to the particulate and sediment samples to determine the detrital and non-detrital fractions. These experiments showed that in general about 80-100% Mn, 60% Zn and 20% Cu were in the non-detrital form. Rank order correlation tests of the sediment results showed that the summer profiles were consistently different to 20 randomly generated profiles of the same data. In contrast the winter distribution …

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Pronoun Interpretation In Reading, Edward Lionel Whitehead Jan 1983

Pronoun Interpretation In Reading, Edward Lionel Whitehead

School of Psychology Theses

This research investigated the comprehension of anaphoric pronouns in reading. Chapter, I explains the importance of this feature of text processing, and reviews the relevant psychological literature. One -important feature of pronoun interpretation is the fact that antecedents vary in accessibility in response to aspects of text content and structure; antecedents which are readily acessible to pronominal reference are said to be foregrounded. The most common theoretical explanation of foregrounding is the claim that foregrounded antecedents are held in working memory. The review also shows reasons why good and poor readers might differ in sensitivity to foregrounding. Experiments 1-3 investigated …

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Studies Of Arsenic, Copper And Lead In The Soils Of The Tamar Valley, Stephen John Haswell Jan 1983

Studies Of Arsenic, Copper And Lead In The Soils Of The Tamar Valley, Stephen John Haswell

School of Geography, Earth and Environmental Sciences Theses

A more detailed soil survey than had previously been carried out in the Tamar Valley area of South West England confirmed higher than normal background levels of arsenic, copper and lead. These elevated background levels are attributed to the weathering of mineralized bed rock. Anomalous values were found directly above mineralized veins and in areas of past mining activity. Effects of aerial pollution are indicated by the combination of sodium dithionite and nitric acid extraction techniques, from which elemental association with secondary iron and sulphide minerals may be determined. Enhanced levels resulting from aerial pollution were found in a zone …

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Carbon And Coke Reactivity In Zinc-Lead Blast Furnace Practice, Margaret Ann Carter Jan 1983

Carbon And Coke Reactivity In Zinc-Lead Blast Furnace Practice, Margaret Ann Carter

School of Geography, Earth and Environmental Sciences Theses

Previous research on the oxidation of coke in air, O2 and CO2 has been reviewed, especially with regard to kinetic studies and Zn/Pb blast furnace practice. Coke "reactivity" has been discussed and correlated with surface area changes on carbon burn-off (in air and CO2 at various temperatures) for Nauitgarw and two other metallurgical cokes. Other carbons (charcoals and graphite) and a-brovnr. coal char~ have been examined by gas sorption, X ray diffraction and thermal analysis in an attempt to relate reactivity, as determined by rate of reaction in CO2 at 1000°C, with other solid state properties. Reactivity studies on coal …

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Hydrogeological Investigations In A Granite Catchment, Dartmoor, Devon, Jean Alexander Jan 1983

Hydrogeological Investigations In A Granite Catchment, Dartmoor, Devon, Jean Alexander

School of Geography, Earth and Environmental Sciences Theses

A network of 13 observation wells were utilized in the Narrator Brook Catchment, Dartmoor, Devon, to monitor groundwater level fluctuations, in an attempt to assess the water resource potential of a weathered granite aquifer. Meteorological parameters, soil moisture data and reservoir levels together with waterlevel observations were used in a stepwise regression model with a view to predict and account for the behaviour of groundwater levels in weathered granite areas. Variations in groundwater and surface water chemistry were used as a basis for the hydrogeological grouping of the wells in the valley, whose individual characteristics were determined by site topography, …

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The Dispersal Of Cabbage Root Fly In Relation To Agricultural Practice, Kirk I. Alexander Jan 1983

The Dispersal Of Cabbage Root Fly In Relation To Agricultural Practice, Kirk I. Alexander

Other Faculty of Science and Engineering Theses

The study aimed to estimate the dispersal rate of wild cabbage root flies in agricultural systems, to test a migration hypothesis and the predictions of a computer simulation model. The dispersal rate was determined by a new method, from the age-grouping of wild flies instead of releasing marked culture flies. The mean distance dispersed was calculated from-the slope of density of captured flies on distance; the mean age was calculated from laboratory measurements of development at constant temperatures. A new method of male age determination was developed, based on the changes in pupal fat and testes colour. The published method …

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The Effects Of A Program Of Therapeutic Horsemanship On The Self-Concept And Locus Of Control Orientation Of The Learning Disabled, Eugene Alfred Carlson Jan 1983

The Effects Of A Program Of Therapeutic Horsemanship On The Self-Concept And Locus Of Control Orientation Of The Learning Disabled, Eugene Alfred Carlson

Other Faculty of Arts, Humanities and Business Theses

The last decade has witnessed a growing trend toward developing new ways in which human beings may benefit from the creative and non-exploitative use of animals. These animals, generally having some special or unique quality and often referred to as companion animals or pets, have demonstrated a therapeutical value for many persons far beyond the parameters of simple recreation. More specifically, the animals have shown many times over their value as therapeutical adjuncts for the handicapped; a well-known example developed early in this century being the use of guide dogs for the blind. More recent developments are organized horseback riding …

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Successive Incentive Contrast: Implications Of Deconfounded Procedures, Janet M. Collis Jan 1983

Successive Incentive Contrast: Implications Of Deconfounded Procedures, Janet M. Collis

School of Psychology Theses

This thesis reports a series of investigations into the incentive contract effect. From a review of the literature, it was concluded that a clear distinction should be made between the effects of conventional and deconfounded contrast procedures. Different experimental apparatus also appeared to be important in determining subsequent effects of reward magnitude shifts. The present investigations consisted of six experiments employing a deconfounded procedure and one experiment employed a conventional procedure. Experiment I established contrast effects with a free operant deconfounded procedure. Experiment II showed that previously established runway contrast effects (with a conventional procedure) could be used in subsequent …

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Production And Properties Of Extracellular Factors From Aeromonas Salmonicida, Richard W. Titball Jan 1983

Production And Properties Of Extracellular Factors From Aeromonas Salmonicida, Richard W. Titball

School of Biological and Marine Sciences Theses

The production of extracellular products by Aeromonas salmonicida, in vitro, has been investigated. The results indicated that the bacterium produces at least two haemolytic activities in vitro. Unshaken cultural conditions favoured the production of a haemolysin with a broad spectrum of activity against various erythrocyte types (H-lysin), whilst shaken cultural conditions favoured the production of a haemolysin active against trout erythrocytes (T-lysin). The effects of growth medium type and culture conditions on the production of these haemolytic activities has been investigated. The activity of the T-lysin appeared to be attributable to the combined effects of an activity which caused incomplete …

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The Mechanical Properties Of Carbon Fibre With Glass Fibre Hybrid Reinforced Plastics, John Summerscales Jan 1983

The Mechanical Properties Of Carbon Fibre With Glass Fibre Hybrid Reinforced Plastics, John Summerscales

School of Engineering, Computing and Mathematics Theses

Fibre composite hybrid materials are generally plastics reinforced with two different fibre species. The combination of these three materials (in this thesis they are carbon fibres, glass fibres and polyester resin) allows a balance to be achieved between the properties of the two monofibre composites. Over the fifteen years since the introduction of continuous carbon fibre as a reinforcement, there has been considerable speculation about the "hybrid effect", a synergistic strengthening of reinforced plastics with two fibres when compared with the strength predicted from a weighted average from the component composites. A new equation is presented which predicts the extent …

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The Biology Of British Marine Hemiuridae, Brenda Fay Matthews Jan 1982

The Biology Of British Marine Hemiuridae, Brenda Fay Matthews

School of Biological and Marine Sciences Theses

The cystophorous hemiurid cercariae, Cercaria vaullegeardi and C. calliostomae, are recorded from the digestive gland of Gibbula umbilicalis and the gonad of calliostoma ziziphinum respectively. The encysted forms are described at ultrastructural level for the first time, and developmental stages redescribed. Specialisation of the anterior region and birth pore of the daughter sporocyst in c. vaullegeardi, and migration of the redia in C. calliostomae, ensure that in neither species does the cercaria, hindered by a bulky immotile cystophorous tail, itself have to migrate through blood vessels or tissues to the site of emergence from the molluscan host. The inoculative mechanism …

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The Interaction Of Phosphate With Iron Oxyhydroxides In Simulated Estuarine Conditions, Stuart Arthur Crosby Jan 1982

The Interaction Of Phosphate With Iron Oxyhydroxides In Simulated Estuarine Conditions, Stuart Arthur Crosby

School of Biological and Marine Sciences Theses

The uptake of phosphate onto Fe(II) and Fe(III) derived iron oxyhydroxides was examined as a function of time using conditions similar to those encountered in natural waters. The freshly precipitating Fe(III) oxyhydroxide was very active and its adsorption behaviour was independent of pH, temperature and ionic strength. The adsorption onto freshly precipitating Fe(II) derived oxyhydroxide was strongly dependent on all three factors as the rate of uptake was limited by the rate of oxidation and hydrolysis of Fe(II) .

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The Evaluation Of Wave Forces On Seawalls, Paul Blackmore Jan 1982

The Evaluation Of Wave Forces On Seawalls, Paul Blackmore

School of Engineering, Computing and Mathematics Theses

This Thesis is divided into two parts, Part A deals with the measurement and analysis of wave pressures on real seawalls and Part B deals with the resulting structural response of these seawalls. There have been only thirteen previous investigations to measure full scale wave impact pressures on coastal structures, and of these only five were conducted with sensitive electronic measuring equipment. The infrequent occurrence of impact pressures in a real sea has meant very little impact pressure data has been collected by these previous investigations. This investigation is the first of its kind to be carried out in the …

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Luminance Design A Simulation Using Colour Television, D. J. Gilderdale Jan 1982

Luminance Design A Simulation Using Colour Television, D. J. Gilderdale

School of Engineering, Computing and Mathematics Theses

A successful lighting design usually results from the skill of the designer in applying professional experience. However, successful designs have been achieved using numerical prediction. It is probable that a blend of both these elements will give the optimum result. Whatever the design approach, the end product will be judged, at least in part, on its aesthetic merits. The first chapter of this thesis introduces the possibility of using a digital computer in conjunction with a colour television monitor to calculate and display the luminance distribution in a lighted room; a system which may offer advantages both for the experienced …

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Novel Approaches To Trace Metal Speciation, Robert William Ward Jan 1982

Novel Approaches To Trace Metal Speciation, Robert William Ward

School of Geography, Earth and Environmental Sciences Theses

It is now generally recognised that the form of metal occurrence affects the toxicity, availability and transport mechanisms of different metals. One promising method for measuring trace metal speciation is to separate the various forms chromatographically and detect these by atomic spectroscopy. The suitability of the various atomic spectroscopic techniques is discussed and their coupling to both gas and liquid chromatography reviewed.

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Polycyclic Aromatic Hydrocarbons In The Tamar Estuary, James Readman Jan 1982

Polycyclic Aromatic Hydrocarbons In The Tamar Estuary, James Readman

School of Geography, Earth and Environmental Sciences Theses

The high particulate association of PAH in aquatic systems has often been attributed to the hydrophobic nature of the compounds leading to adsorption. Results presented i n this thesis strongly suggest that a significant proportion of PAH in the Tamar are particle-incorporated and unavailable for dynamic partition and physical, chemical and biological fates. The generally uniform PAH composition identified throughout the estuary is highly indicative of a combustion or road and urban runoff source. PAH distrubution in a dated Tamar Estuary sediment core showed an exponential decrease with depth and identified dramatic increases in PAH flux during the last 20 …

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The Interaction Between Nurses And Patients' Relatives, Ruth Hawker Jan 1982

The Interaction Between Nurses And Patients' Relatives, Ruth Hawker

School of Nursing and Midwifery Theses

During the course of a span of duty the nurse in hospital has to relate to a number of different people including other occupational groups, other nurses, patients and patients' relatives. The present study has been designed to examine one of these role-relationships, that between the nurse and the patients' relatives.

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Magnetostriction Harmonics In (110) [001] Silicon - Iron, C.E. White Jan 1982

Magnetostriction Harmonics In (110) [001] Silicon - Iron, C.E. White

School of Geography, Earth and Environmental Sciences Theses

The contribution of the harmonics of magnetostriction to the overall noise spectrum of power transformers is discussed with reference to the domain theory of ferromagnetism, the development of electrical steels and transformer design, and current sound measurement practice.

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The History Of Libraries In Plymouth To 1914: A Study Of The Library Developments In The Three Towns Of Plymouth, Devonport And Stonehouse Which Amalgamated Into Plymouth In 1914, Margaret Ivy Lattimore Jan 1982

The History Of Libraries In Plymouth To 1914: A Study Of The Library Developments In The Three Towns Of Plymouth, Devonport And Stonehouse Which Amalgamated Into Plymouth In 1914, Margaret Ivy Lattimore

Other Faculty of Arts, Humanities and Business Theses

The individual and collective history and character of the Three Towns is outlined, with special reference to factors affecting their potential as library environments. The libraries are then presented by type, each type being introduced by an appropriate sketch of the national setting and specialist local background, followed by accounts of individual libraries. The libraries are mostly post-1800, and the main types are: commercial subscription, private subscription, literary and philosophical, mechanics' institutes, cooperative, rate-supported, school, scientific, medical, law and naval libraries. The general conclusions reached are: that the Three Towns contained a number of libraries which were amongst the earliest …

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