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Investigation of the DNA binding domain of nuclear factor IFreeman, Alasdair D. J. January 1999 (has links)
Nuclear Factor I is a cellular transcription factor involved in the initiation of adenovirus type 2 replication. It exists as a family of proteins and comprises two distinct domains. The N-terminal domain is highly conserved between species and is involved in DNA binding, dimerisation, and stimulates adenovirus replication. The C terminal domain is responsible for the transcriptional activation. In this work, the N terminal, DNA binding domain of Nuclear Factor I, was cloned in two different expression systems. Using recombinant baculovirus, the unmodified protein and a GST fusion product were expressed in insect cells. Although both proteins were expressed at high levels, it was impossible to purify the fusion protein, while after purification, the unmodified protein remained heterogeneous. Expression in E. coli using the expression vector pET22b and pGEX2T produced inclusion bodies. The insoluble material was extracted, solubilised using guanidine HCl, then folded in vitro using new additives known as non-detergent sulphobetaines. In vitro folding was optimised and yields of up to 8% could be obtained. The affinity of the refolded material for a specific DNA oligonucleotide was determined in a gel electrophoresis DNA binding assay and was identical to the native protein purified from baculovirus infected insect cells. The structure of the Nuclear Factor I DNA Binding Domain was investigated using limited proteolysis followed by separation on SDS PAGE, N terminal sequencing and mass spectrometry. Residues 1 to 165 formed a compact domain. Residues 166 - 181 were extremely sensitive to degradation in the absence of DNA but fully protected in the presence of specific DNA. The C terminal region from residue 182 could be degraded in both conditions. Along with two other regions previously determined which bind DNA, the region between residues 166 and 181 is required for DNA binding. Differential labelling using iodoacetate showed that cysteine residues 95 and 111 were modified in the free protein which resulted in an inactive protein but were protected in the presence of DNA. This demonstrates their direct involvement in DNA binding.
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The effect of social stereotypes on eyewitness behaviourFrowley, Jason N. January 1994 (has links)
Eyewitness behaviour is a very important issue in social psychology. Recent years have seen a boom in research in this area; however, very little of this research has addressed the important and fundamental issues raised by the social factors that are involved when eyewitnessing takes place. The present thesis reports research which addresses the effect of social- stereotypic information upon a number of aspects of the eyewitness situation. Of particular interest is the effect of stereotypic information upon the judgment of aggressive and violent actions, and face and body stimuli; on memory for information associated with a dramatic staged incident, when presented either before or after target material; and its impact in an eyewitness interview situation. Finally, an interview technique is designed and tested which aims to reduce the negative impact of stereotypic information on eyewitness memory. Throughout, the impact of stereotypic information presented at encoding and at retrieval is contrasted and compared. The effect of delay between encoding and retrieval is also considered. It is concluded that stereotypic information may affect judgments of information relevant to the eyewitnessing situation whether presented before or after target material. Similarly, stereotypic information may affect memory when it is presented before target material. Little effect is however to be expected on memory when stereotypic information is presented at retrieval, although the exact effects may be found to vary with the nature of the target stimuli used. The source-monitoring interview, based on research by Marcia Johnson and her colleagues, appears a promising means of reducing the distorting effect of stereotypes on memory; particularly when a delay occurs between the encoding and retrieval of target material.
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CyclopentadienylidesFreeman, Brian Harding January 1971 (has links)
The thermal decomposition of 2,3,4,5-tetraphenyldiazocyclopentadiene in the presence of carbene acceptors having Group V and VI elements to give 2,3,4,5-tetraphenylcyclopentadienylides has been extended and the first example of a telluronium ylide has been prepared by this method. The procedure has also been extended to other substituted diazo-cyclopentadienes and various new phosphonium, arsonium and sulphonium ylides have been prepared. The reaction of diazocyclopentadienes with triphenylphosphine to give either phosphazines or phosphonium ylides has been studied and the reasons for the difference in reactivity of these diazo-compounds has been clarified to some extent. It has been shown that for phosphazine formation both lack of steric hindrance and the absence of an electron- donating group on the cyclopentadiene ring are required. The thermal reaction of diazocyclopentadienes is assumed to proceed via a carbene-type intermediate which is then attacked by the reagent present to give an ylide. This reaction can be catalysed by the presence of copper-bronze and, in this case, can be effected either under melt conditions or in solution. The stability of the carbenoid intermediate is demonstrated by its preferential reaction with triphenylarsine rather than with benzene, which is present as the solvent. The reaction of 2,5-diphenyldiazocyclopentadiene with triphenylarsine gives a rearranged 2,4-disubstituted product. The carbene-type intermediate in this case is presumed to rearrange before reaction with the triphenylarsine. Some cyclopentadienylidene triphenylphosphazines have been shown to decompose thermally in the presence of triphenylphosphine to give the related triphenylphosphonium ylides. Diazocyclopentadienes have been found to react with either hydrochloric or hydrobromic acid to give the monochloro or monobromo cyclopentadienes. The parent, unsubstituted triphenylarsonium cyclopentadienylide has been prepared by the reaction of triphenylarsine with dibromocyclopentene and basification of the bis-arsonium salt so formed. Its properties and reactions have been studied and are found to be similar to the analogous triphenylphosphonium ylide. The salt method for the preparation of cyclopentadienylides has also been investigated. Triphenylarsine has been shown to react with 5-bromo-1,2,3-triphenylcyclopentadiene in solution at room temperature to give the hydrobromide salt of the ylide. Various sulphides also reacted with the bromo-compound to give, in most cases, unexpected products. The reactions of the cyclopentadienylides prepared with aldehydes have been investigated and the results are in line with previous findings. The cyclopentadienylides also readily undergo electrophilic substitution on the five-membered ring. The reaction proceeds preferentially at the 2(5)-position.
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Physiology of the adrenocortical tissue in the whitefish, Coregonus lavaretus, LinnaeusFuller, Joan D. January 1974 (has links)
No description available.
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The theory of eucharistic presence in the early Caroline divines, examined in its European theological settingFrank, Gary Lee Chrysostom January 1985 (has links)
The question of Christ's presence in the eucharist was an issue which caused great controversy in the Reformation period, and which continued to evoke dispute during the seventeenth century. Various interpretations of the Caroline divines' teaching on the eucharistic presence have been offered, but often they seem either to indicate the theological position of the writer rather than that of the theologians considered, or to ignore the broader context of eucharistic doctrine. The purpose of this study, therefore, was 1. to investigate the theology of eucharistic presence in the thinking of several seventeenth-century Anglican divines, and 2. to examine their teaching in relation to the sixteenth-century Anglican heritage and the various continental sacramental doctrines, Reformed, Lutheran, Roman Catholic and Eastern Orthodox. To accomplish this goal, eight theologians were chosen for examination: Adrianus Saravia, Lancelot Andrewes, John Cosin, Richard Montague, William Forbes, William Laud, Jeremy Taylor and Herbert Thorndike. When available, nineteenth-century editions of their works were used; otherwise, seventeenth-century texts were employed. Similarly, modern editions of Roman, Orthodox, Lutheran and Reformed writings were utilized when possible. Thy examination of eucharistic teaching included seven major points: 1. the sacrament as mystery, 2. eucharistic change, 3. the relationship between Christ's body and the bread, 4. eucharistic communion, 5. the nature of Christ's body in the sacrament, 6. consecration, and 7. adoration in the eucharist. This study has shown that there was great diversity in the thinking of the Caroline divines (although they did not treat the subject of eucharistic presence with equal detail or depth); no unified understanding of sacramental presence was expressed. Reformed ideas inherited from the previous century remained strong, but new tendencies toward other understandings of the eucharist can be discerned. The period, therefore, can be seen to represent a new stage in the history of Anglican eucharistic doctrine.
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Second-order logic is logicFriend, Michèle Indira January 1997 (has links)
"Second-order logic" is the name given to a formal system. Some claim that the formal system is a logical system. Others claim that it is a mathematical system. In the thesis, I examine these claims in the light of some philosophical criteria which first motivated Frege in his logicist project. The criteria are that a logic should be universal, it should reflect our intuitive notion of logical validity, and it should be analytic. The analysis is interesting in two respects. One is conceptual: it gives us a purchase on where and how to draw a distinction between logic and other sciences. The other interest is historical: showing that second-order logic is a logical system according to the philosophical criteria mentioned above goes some way towards vindicating Frege's logicist project in a contemporary context.
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Novel bulky fluorinated ligands for homogeneous catalysisFrew, Jamie J. R. January 2008 (has links)
A series of novel monodentate and bidentate phosphine ligands substituted with bulky tert-butyl and fluorinated aryl groups have been synthesised. Borane protection has proved to be an excellent method for easy synthesis and purification of bidentate ligands in some cases. However, several of the bulky fluorinated ligands do not form stable borane complexes leading to complications in the synthesis and purification of these compounds. By reaction with transition metal platinum and palladium precursors, it was possible to form dichloride complexes from the synthesised ligands, which were characterised by X-ray crystallography. The complexes were found to be effective catalysts for the hydroxycarbonylation of vinyl arenes (yields of up to 95 % with 3 mol% catalyst). An unsymmetrical bidentate complex (3.18) in combination with paratoluenesulfonic acid and LiCl promoters has given exceptional (for a diphosphine ligand) regioselectivity for the branched acid (98.7 % branched) in the hydroxycarbonylation of styrene. The role of the promoters has been found to be crucial in deciding the activity and selectivity in this reaction.
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Memory expansion of the Fairchild F8 MicroprocessorLinhares, Patrick Haven, 1945- January 1976 (has links)
No description available.
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The dream state : making, reading and marketing contemporary Scottish poetryFraser, Lilias January 2003 (has links)
This thesis investigates aspects of the writing, reading, and marketing of contemporary Scottish poetry, suggesting that readers of contemporary poetry are influenced in their reading by marketplace forces as well as by their early academic training. The thesis attempts to reflect this combination of influences on the reader, but it also seeks to reflect the awareness of these influences in the poets' work. The Dream State concentrates on factors which condition the reading of contemporary Scottish poetry, and on some of the poetry of seven poets who became established in the 1990s: John Burnside, Robert Crawford, W. N. Herbert, Tracey Herd, Kathleen Jamie, Don Paterson and Robin Robertson. Alert to the political climate of Scottish devolution and to a literary climate which saw the simultaneous appearance of the anthology Dream State: The New Scottish Poets and the 1994 New Generation poetry promotion, the thesis examines the pressures of expectation on these Scottish poets writing in English and Scots during the 1990s. The thesis argues that the complexity of their poems and jobs as poets in this period is best understood by 'thinking together' (Steven Connor) the principles of Practical Criticism and publishing history's approach to literature in the marketplace; I draw on research fi-om a combination of critical sources in literary theory and criticism, book history and interviews/correspondence with poets, teachers and the booktrade. Chapters describing critical narratives which can pre-empt reading - the theoretical spaces of contemporary Scottish poetry, the origins of Practical Criticism, and academic/commercial expectations of the reader - are followed by chapters on the work of these seven poets. Chapter 4 examines longer poems as a reflection of the poets' concerns about personal and national identity, and Chapter 5 discusses the poets' exploration of their social and literary environments. The Conclusion discusses the significance of what I term the museum poem and of anthologies of twentieth-century Scottish poetry, drawing on Walter Benjamin's Arcades Project for an appropriate model of contemporary reading.
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FPGA-Based Implementation of a Digital Processor for an Instantaneous Frequency Measurement ReceiverHelton, James M. 28 September 2007 (has links)
No description available.
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