No description available.

In this thesis we start by considering conditions under which some standard semigroup constructions preserve automaticity. We first consider Rees matrix semigroups over a semigroup, which we call the base, and work on the following questions: (i) If the base is automatic is the Rees matrix semigroup automatic? (ii) If the Rees matrix semigroup is automatic must the base be automatic as well? We also consider similar questions for Bruck-Reilly extensions of monoids and wreath products of semigroups. Then we consider subsemigroups of free products of semigroups and we study conditions that guarantee them to be automatic. Finally we obtain a description of the subsemigroups of the bicyclic monoid that allow us to study some of their properties, which include finite generation, automaticity and finite presentability.

The synthesis of a variety of polynuclear aromatic hydrocarbons by means of the condensation of grignard reagents with aromatic aldehydes did not always lead to the isolation of the desired diarylcarbinols. The delicate relationship between molecular structure and physiological activity demanded that only pure compounds of known structure be used in studying the carcinogenic and/ or carcinolytic effects of these aromatic hydrocarbons. Therefore, the above method of synthesis was eventually by-passed. But the apparently "abnormal" condensation of grignard reagents with aromatic aldehydes and the thermal decomposition of diarylcarbinols at high temperatures generated a great deal of interest from the mechanistic point of view, and these reactions were studied in detail in this work. The previously unreported ketones, 2-fluorophenyl 1-naphthyl ketone (52) and 2-fluorophenyl 2-naphthyl ketone (53), were prepared by the condensation of the cadmium reagents of 1- and 2-bromonaphthalene with 2-fluorobenzoyl chloride (51). Reduction of these ketones, 52 and 53, with a mixture of lithium aluminum hydride and aluminum chloride afforded the corresponding diarylmethanes, 2-(1-naphthylmethyl)fluorobenzene (56) and 2-(2-naphthylmethyl)fluorobenzene (57), respectively. Reduction of these same ketones, 52 and 53, with sodium hydroborate afforded the corresponding diarylcarbinols, 2-fluorophenyl-1-naphthyl carbinol (54) and 2-fluorophenyl-2-naphthyl carbinol (55), in good yield. The previously unreported 1-bromo-2-(1-naphthyl)naphthyl carbinol (45) was prepared by reduction of 1-bromo-2-(1-naphthyl) naphthyl ketone (44) with sodium hydroborate. This diarylcarbinol 45 was also prepared via the reaction of the Grignard reagent of 1-bromonaphthalene with 1-bromo-2-naphthaldehyde (41). The proof of structure of 45 was accomplished by studying the nuclear magnetic resonance and infrared spectra of 45 in conjunction with the nuclear magnetic resonance and infrared spectra of 1-bromo-2-(1-naphthyl)naphthyl carbinol-OD₁ (46) and 1-bromo-2-(1-naphthyl)naphthyl carbinol-CD₁ (47). The reported "abnormal" reaction of the Grignard reagents was investigated. The reaction of one equivalent of the Grignard reagent of 2-bromonaphthalene with one equivalent of 2-chlorobenzaldehyde gave the expected 2-chlorophenyl-2-naphthyl carbinol (37). The reaction of two equivalents of 2-chlorobenzaldehyde with one equivalent of the Grignard reagent of 2-bromonaphthalene gave 2-chlorophenyl 2-naphthyl ketone (36) by oxidation of the alkoxide complex formed by the initial condensation of the Grignard reagent with the aromatic aldehyde. The high temperature decomposition of diarylcarbinol 45 was found to lead to the formation of sym. -1-bromo-2-(1-naphthyl)naphthylmethyl ether (58). The structure of 58 was confirmed by molecular weight studies, infrared and nuclear magnetic resonance spectra and elemental analyses. The decomposition of ether at 58 240° was found to proceed slowly with the liberation of hydrogen bromide gas. Free radical initiators and hydrogen bromide gas were found to accelerate the decomposition of 58 at 240°. A reasonable mechanism has been postulated for the decomposition of 58 at 240°. The cleavage of ether 58 in the presence of hydrogen bromide gas would give rise to the formation of a secondary bromide, 1-bromo-2-(1-naphthyl)naphthylmethyl bromide (62). Homolysis of 62 would then give a bromine atom and a secondary free radical, 1-bromo-2- (1-naphthyl)naphthylmethyl free radical (63). The attack of free radical 63 on the benzylic hydrogen atoms of ether 58 is thought to be responsible for the formation of the diarylmethane, 1-bromo-2-(1-naphthylmethyl) naphthalene (48) and 1-brome-2-(1-naphthyl)naphthylmethyl ether free radical (64). Homolysis of 64 would then regenerate the secondary free radical 63 and the ketone 44. The coupling of two secondary free radicals 63, with subsequent attack of bromine atoms on the system, might give rise to the formation of di-[1-bromo-2-(1-naphthyl)naphthyl] ethylene (66). The attack of hydrogen atoms on 63 might lead to the formation of diarylmethane 48. Oxidation of ethylene 66 might give rise to the isolation of ketone 44. Evidence for these two reactions has been furnished by the vacuum distillation of secondary bromide 62. The attack of bromine atoms on the benzylic hydrogen atoms of ether 58 would give ether free radical 64 and hydrogen bromide gas. Homolysis of 64 would then give ketone 44 and secondary free radical 63. The decomposition of 58 would then appear to be cyclic in nature. The decomposition of diarylcarbinols 54 and 55 was judged to be free radical in nature, involving the formation of the two ethers, sym. -2-fluorophenyl-l-naphthylmethyl ether (67) and 2-fluorophenyl-2-naphthylmethyl ether (68), which decompose in the same temperature range as 54 and 55. Ethers 67 and 68 were not isolated. The decomposition of 67 and 68 was postulated to be a series of homolytic cleavages, giving rise to the formation of the diarylmethanes, 56 and 57, and the ketones, 52 and 53. / Ph. D.

This thesis examines the use of the trombone in Portugal between the first references to its use in the early sixteenth century and the mid nineteenth century. It is primarily based on archival research and supplemented by literary and iconographical references. This material is presented in calendar form in Volume II as Appendix 1. Volume I consists of a series of chapters that analyse and contextualise material from the Calendar. For the earlier period the thesis focuses on the use of the trombone in royal service, and in doing so provides a detailed survey of the Portuguese royal shawm band. The use of the trombone outwith royal service it is also examined. Issues relating to terminology and instrument making in Portugal are discussed. By examining sixteenth century iconographical sources with links to Portugal, this study addresses questions concerning aspects of trombone technique that have not previously been considered and have implication elsewhere in Europe. It considers the decline of the trombone during the second half of the seventeenth century and its resurgence in the later years of the eighteenth century. It identifies the earliest orchestral repertoire containing trombones that emerges in Portugal during the last decade of the eighteenth century, as well as the first trombone players of the beginning of the nineteenth century in military bands and orchestras in Lisbon. Finally, the thesis considers the class of brass instruments of the Royal Conservatoire of Lisbon and its professors, and examines the earliest surviving trombone methods in Portugal, which introduce aspects of performance practice that are not mentioned in other contemporary sources.

The management of the high volume and different types of information that characterize its projects, has traditionally posed a constant challenge to the architecture, engineering and construction industry. The distribution and communication of such information to project participants, who are often geographically dispersed, is an important necessity and forms a significant part of this challenge. Hypermedia computing on the Internet has emerged as an important and efficient means for the distribution and communication of information. This thesis proposes hypermedia computing on the Internet as a solution to address the problem of information distribution in the architecture, engineering and construction industry. The problem of information management is examined, and relevant features of hypermedia and the Internet discussed. The viability of the technology to address the specific problem of information communication and distribution is demonstrated by building a hypermedia based information system as proof of concept. The thesis concludes with a discussion of future developments in this technology and the scope for further work in hypermedia based information distribution systems. / Master of Science

The purpose of this thesis is to explore the reasons why readers choose to read detective fiction. Taking Thomas De Quincey's satirical identification of the aesthetic quality of murder, I look at Edgar Allan Poe's detective fiction to find a non-satiric version of the same argument that emphasises the balancing quality of the ethical to the aesthetic. W.H. Auden's essay “The Guilty Vicarage” offers an argument concerning the reader's position in relation to these opposite components. I explore the ways in which Auden's arguments build into Freud's understanding of guilt, daydreams, the moral conscience, jokes, the uncanny and the death drive, and how these can be applied to the genre to help illustrate the reader's experience. Concurrent to this I offer an analysis of how the parallel developments in literary theory, particularly those of Barthes and Shklovsky, can be incorporated to enrich the understanding of these Freudian positions within the modern reader's experience. It is my intention to open up a field of study within the genre that differs from the traditional Marxist approach. Particular emphasis is placed on the role of the experience of pleasure found when moments of commonality between the aesthetic and the ethical are reached– how these are often unsatisfactory– necessitating a repetition of the literary experience. It is my argument that such an approach to the reader's position within the genre has not been explored in such a detailed fashion, centring as it does upon the active role of guilt in pleasure felt by the reader as the motivation to repeat. To illustrate that this is an argument that is applicable to different historical phases of detective fiction the study undertakes analysis of the following authors: Arthur Conan Doyle, Wilkie Collins, Agatha Christie, Raymond Chandler, Graham Greene and John Fowles.

Organofluorine compounds find various applications ranging from pharmaceuticals to refrigerants, insecticides, high-value fluoropolymers and reagents in catalysis. However, the synthesis of organofluorine compounds depends on toxic chemicals such as hydrogen fluoride, chlorinated hydrocarbons, reactive F2 gas and environmentally persistent long-chain fluorosurfactants. Recently more sustainable, energy-efficient syntheses have been developed using base metal-catalyzed transformations of fluoroalkenes and the formation and functionalization of d6-8 fluorometallacycles. In this thesis, we use manganese complex precursors to prepare the first examples of d4 fluorometallacycles. Work in Chapter 2 describes the synthesis and one-electron reduction of manganese bis(diphosphine)- and tetrakis(phosphite) dibromide complexes, MnBr2(P-P)2 and MnBr2[P(O-i-Pr)3]4 and reactions of the corresponding reduced Mn(I)Br complexes with tetrafluoroethylene (TFE). Products proposed to be d4 perfluorometallacycles, MnBr[-CF2(CF2)2CF2-](P-P) proved to be unstable, reforming TFE upon application of vacuum. In Chapter 3 we show that photolysis of ligated manganese(I) carbonyl bromide complexes, MnBrLn(CO)5-n, in the presence of TFE, chlorotrifluoroethylene (CTFE) or perfluoro(methyl vinyl ether) (PMVE) in tetrahydrofuran affords the Mn-H insertion products, Mn(CF2CFXH)(L2)(CO)3 (X = F, Cl, OCF3) only for L2 = DPPE [1,2-bis(diphenylphosphino)ethane] as well as a solid by-product proposed to be MnBr2Ln. These reactions are accompanied by THF fluoroalkylation products, O[-(CH2)3CH(CF2CFHX)-]. By switching to methyl t-butyl ether solvent, we showed that exhaustive photolysis of MnBr(CO)5 + 3 equiv. of DPPE gave a new product proposed to be the first stable d4 fluorometallacycle, MnBr[-(CF2)4-](CO)(DPPE). Reactions of the fluoroalkenes with zerovalent Mn2(CO)10 also contributed to our understanding of potential reaction pathways to form these Mn-H-derived products. Previous work in the Baker group compared FeH2(dmpe)2 and [FeH(H2)(dmpe)2]+ as catalysts for the dehydrogenation of amine-boranes [dmpe = 1,2-bis(dimethylphosphino)ethane]. In Chapter 4 the catalytic reactivity and selectivity of MnH(H2)(dmpe)2 are compared with those observed using the Fe analogs and the catalyst resting state, Mn(2-BH4)(dmpe)2, is identified. Finally, in Chapter 5 we summarize the findings of this thesis and suggests future directions based on this work.

This dissertation studies systems of "competing" discrete random walks as discrete and continuous time processes. A system is thought of as containing n imaginary particles performing random walks on lines parallel to the x-axis in Cartesian space. The particles act completely independently of each other and have, in general, different starting coordinates. In the discrete time situation, the motion of the n particles is governed by n independent streams of Bernoulli trials with success probabilities p₁, p₂,…, and p_n respectively. A success for any particle at a trial causes that particle to move one unit toward the origin, and a failure causes it to take a "zero-step" (i.e. remain stationary). A probabilistic description is first given of the positions of the particles at arbitrary points in time, and this is extended to provide time dependent and independent probabilities of which particle is the winner, that is to say, of which particle first reaches the origin. In this case "draws" are possible and the relevant probabilities are derived. The results are expressed, in particular, in terms of Generalized Hypergeometric Functions. In addition, formulae are given for the duration of what may now be regarded as a race with winning post at the origin. In the continuous time situation, the motion of the n particles is governed by n independent Poisson streams, in general, having different parameters. A treatment similar to that for the discrete time situation is given with the exception of draw probabilities which in this case are not possible. Approximations are obtained in many cases. Apart from their practical utility, these give insight into the operation of the systems in that they reveal how changes in one or more of the parameters may affect the win and draw probabilities and also the duration of the race. A chapter is devoted to practical applications. Here it is shown how the theory of random walks racing toward the origin can be utilized as a basic framework for explaining the operation of, and answering pertinent questions concerning several apparently diverse situations. Examples are Lanchester Combat theory, inventory control, reliability and queueing theory. / Ph. D.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-14T19:01:30Z No. of bitstreams: 1 MarinildeSouza.pdf: 1783855 bytes, checksum: bc20000b025261af153ffc4f6418fad7 (MD5) / Made available in DSpace on 2017-06-14T19:01:30Z (GMT). No. of bitstreams: 1 MarinildeSouza.pdf: 1783855 bytes, checksum: bc20000b025261af153ffc4f6418fad7 (MD5) Previous issue date: 2016-05-20 / Introduction: The hepatitis B virus (HBV) present diversity of its genome, which is to be classified in different genotypes and subgenotypes (A-J). It has been demonstrated that different genotypes are related to the natural history of infection. The maintenance of viral replication could be one of the factors related to genotypes. Objectives: To identify the viral replication status of HBV carriers among the subgenótipos A1 and D4. Materials and methods: HBV carriers identified have been studied in two studies involving individuals from the state of Maranhão, northeast,Brazil, which had genotyping and subgenotypes, serology for HBeAg and anti-HBe and certain viral loads. Serological tests were performed by ELISA, HBV – DNA quantification real time PCR and genotyping performed by sequencing. Results: We identified 146 patients. Among these, 136 were subgenotype A1 or D4. It is 85 - A1 (62.5%) and 51 - D4 (37.5%). No difference was found between groups when age was evaluated (42 ± 12 vs 38 ± 17 p=0.11) or gender (male 48.5% vs 51.5% p=00.18). Among the D4 subgenotype carriers had more patients with HBeAg positive (23.5% vs 9.4%, p=0.02) and a higher proportion of patients with viral loads above 20.000 IU / ml (43.1% vs 12.9 % p <0.0001), even when only those with negative HBeAg (25.6% vs 6.5%, p=0.007) when compared with the A1 subgenotype. Conclusion: HBV carriers, subgenotype D4, compared to A1 subgenotype have delayed HBeAg seroconversion and higher levels of HBV – DNA, suggesting that this subgenotype is possibly related to / Introdução: O vírus da hepatite B (VHB) apresenta diversidade do seu genoma, o que o faz ser classificado em diferentes genótipos e subgenótipos (A-J). Tem sido demonstrado que os diversos genótipos estão relacionados com a história natural da infecção. A manutenção da replicação viral pode ser um dos fatores relacionado aos genótipos. Objetivos: Identificar o estado de replicação viral do VHB entre portadores dos subgenótipos A1 e D4. Materiais e métodos: Foram estudados portadores do VHB identificados em dois estudos que envolveram indivíduos provenientes do estado do Maranhão, nordeste do Brasil, que tinham determinação de genótipos e subgenótipos, sorologias para o HBeAg e anti-HBe e cargas virais determinadas. Sorologias foram realizadas por ELISA, VHB–DNA quantificado por PCR em tempo real e genotipagem realizada por sequenciamento. Resultados: Foram identificados 146 portadores. Dentre estes, 136 eram subgenótipo A1 ou D4. Sendo 85 - A1 (62,5%) e 51 - D4 (37,5%). Não houve diferença entre os grupos quando foi avaliado idade (42±12 vs 38±17 p=0,11) ou gênero (masculino 48,5% vs 51,5% p=0,18). Entre os portadores do subgenótipo D4 havia mais indivíduos com HBeAg positivo (23,5% vs 9,4%, p=0.02) e maior proporção de portadores de cargas virais acima de 20.000 UI/ml (43,1% vs 12,9% p<0,0001), mesmo quando avaliados apenas aqueles com HBeAg negativos (25,6% vs 6,5% p=0,007), quando comparados com os de subgenótipo A1. Conclusão: Portadores do VHB, subgenótipo D4, quando comparados com subgenótipo A1 apresentam soroconversão mais tardia do HBeAg e maiores níveis de VHB–DNA, sugerindo que esse subgenótipo possivelmente está relacionado com potencial para doença mais grave e maior facilidade de transmissão da infecção.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 4 uppsatser.