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Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-04-04T15:05:19Z No. of bitstreams: 1 SAMARA MARQUES DOS REIS .pdf: 1152921 bytes, checksum: 30f5b5e9c3afbab29666da7f6e7c9033 (MD5) / Made available in DSpace on 2016-04-04T15:05:19Z (GMT). No. of bitstreams: 1 SAMARA MARQUES DOS REIS .pdf: 1152921 bytes, checksum: 30f5b5e9c3afbab29666da7f6e7c9033 (MD5) Previous issue date: 2015-03-04 / Estudos de associação gene-doença mostraram uma relação entre TPH2 e a depressão em diferentes populações, estudos, no entanto, têm sido produzidos resultados contraditórios, sendo a Triptofano hidroxilase-2 (TPH2) uma enzima limitante da taxa na via sintética para a serotonina do cérebro, vários estudos relatam os polimorfismos da enzima TPH2. Dois grandes projetos, o HapMap e o 1000 genomas, organizaram a maioria dos polimorfismos a partir do estudo de várias populações disponibilizando estes dados. Este trabalho tem como objetivo desenvolver um método de estudo para obtenção de possíveis marcadores de predisposição a doença a partir da correlação entre os dados epidemiológicos e frequências populacionais de polimorfismos, baseado na hipótese de que se numa população existe maior frequência de uma determinada patologia determinada geneticamente, então as variantes envolvidas deveriam estar em maior frequência e vice-versa. O modelo usado foi o envolvimento de variantes do gene TPH2 na predisposição à depressão. Os dados obtidos com correlação positiva em um dos genótipos homozigotos e também no alelo deste homozigoto sugeriram a presença de 10 polimorfismos (14,49% do total) possivelmente envolvidos no desenvolvimento do processo depressivo. Estes dados foram comparados com dados da literatura envolvendo estudos do tipo caso controle. Nestes trabalhos foram estudados 20 dos 69 polimorfismos descritos para o gene TPH2. Com exceção de um único polimorfismo, todos os dados obtidos com a nossa estratégia apresentaram-se iguais aos dados da literatura, inclusive quanto ao alelo que determinaria predisposição à depressão quando demonstrada associação. Portanto, propomos esta estratégia como uma forma alternativa de se realizar estudos do tipo Genome-Wide Association sem a necessidade de estudos caso-controle, apenas usando dados epidemiológicos da doença, diminuindo o tempo e custo destes estudos. / Disease-gene association studies reported a relation between the TPH2 and depression in different populations, however some studies have produced contradictory results, being the tryptophan hydroxylase-2 (TPH2) a limiting enzyme in the rate of synthetic route of serotonin in the brain, many studies reported the polymorphisms of the TPH2 enzyme. Two big projects, HapMap and 1000 genomes, organized the major part of these polymorphisms from the study of several populations becoming these data available. This work is aimed to develop a system to obtain possible predisposition markers of a disease from the correlation between epidemiological data and population frequencies of polymorphism, based in the hypothesis that if in a population there is more frequency of a certain kind of pathology genetically determined, the variables involved should be more frequent and vice-versa. The model used was the involvement of variables of the TPH2 gene in the predisposition of depression. The data obtained with positive correlation in one of homozygous genotypes and in the allele of this homozygous suggested the presence of 10 polymorphisms (total 14,49%) possibly related to the development of depression. These data were compared to literature data involving case control studies. In these work were studied 20 from 69 polymorphisms described to the TPH2 gene. With the exception of only one polymorphism, all the data obtained through the strategy proposed in this work have been equals to the literature data, including the allele that is determinant to the predisposition of depression when it is demonstrated the association. Therefore, it is proposed this strategy as an alternative to realize this kind of Genome-Wide Association studies without the necessity of a case control study, only using the epidemiological data from the disease, decreasing the time and the cost of this study.

Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.

Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.

Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.

Theoretical research has demonstrated that ecological interactions in sympatry or parapatry can generate disruptive selection that in concert with assortative mating can lead to speciation. However, empirical examples are few and restricted to terrestrial and lacustrine systems. New Zealand triplefin fishes (Family Tripterygiidae) are an ideal model system to study speciation in the sea, as they conform to the criteria of an adaptive radiation, being philopatric, speciose and abundant, and having largely sympatric distributions. This thesis investigates two key aspects of the New Zealand triplefin radiation: 1) which ecological traits are under selection?; and 2) which traits are potentially available for the development of assortative mating? Habitat use was identified as a possible key trait for selection and investigated in detail in this thesis. Habitat use of the majority of New Zealand triplefin species was censused quantitatively throughout most of their latitudinal range and analysed using novel statistical methods. Analyses showed that habitat use was highly divergent between species and thus diversification in habitat may have been a major component in the evolution of this clade. The phylogenetic analysis of habitat characters confirmed that there has been rapid evolution in habitat use among species. Habitat selection at settlement was highly species-specific, indicating that interspecific differences in adult habitat use may be the outcome of active habitat choice established at settlement. These species-specific habitat associations showed no evidence for geographic variation in habitat use. Laboratory trials and field observations of the sister-species pair Ruanoho decemdigitatus and R. whero showed that competition was linked with body size, with R. decemdigitatus being the larger and consequently dominant species. The second part of this thesis investigated which traits may have contributed to prezygotic isolation, and thus to assortative mating. Little evidence was found for divergence in breeding season or male colour patterns. However, divergence in habitat affected breeding habitat choice, as triplefins court and mate in the same territory as that occupied year round. This suggests that assortative mating in New Zealand triplefin species could be the by-product of adaptation to habitat resources. Body size affected mate choice and time at first maturity in the Ruanoho sister-species pair, suggesting that size is important in the maintenance of reproductive isolation in these species. Differences in body size may have also lead to assortative mating in other New Zealand triplefin sister-species pairs, as all sister-species pairs differ in maximum body size. The findings of this thesis invoke a strong role for ecologically-based selection in speciation, and support the hypothesis that adaptation to habitat has been a major factor in speciation in this system. / This PhD was funded by the New Zealand Royal Society (Marsden Fund 02-UOA-005 to Kendall Clements), the Tertiary Education Commission (Top Achiever Doctoral Scholarship), and the University of Auckland (University of Auckland Doctoral Scholarship.

The study aims to review the regulatory powers exercised by the South African Revenue Services (SARS) with regard to the issuing, decline or revocation of a taxpayer’s tax clearance certificate, to highlight any remedial measures and procedures available to the aggrieved taxpayer in order to protect the right of taxpayers to fair administrative action in their dealings with SARS. Previously, a tax clearance certificate was not issued in terms of any statute or provision of any Tax Act. However, since the introduction of the Tax Administration Act, as amended (TAA), the issuing of the tax clearance certificates are more efficiently regulated. The issuing of tax clearance certificate’s must conform to the values and principles prescribed for under current legislation, and more particularly, as espoused under the Constitution of South Africa, 1996 (the Constitution). However, it has been reported some taxpayer were experiencing unreasonable and incomprehensible delays in obtaining responses to the objections lodged with SARS for assessment. Taxpayers seeking resolution of their disputes with SARS, currently opt to incur litigation costs in order to obtain appropriate relief from the High Courts. Taxpayers must take note that there is nothing in Promotion of Administrative Justice Act (PAJA) or the common law, which empowers a Court to order an administrator to take action, including the making of a decision which the administrator is not lawfully allowed to make. The study highlights remedial measures and procedures available to the aggrieved taxpayer to prevent the misapplication of fiscal power by SARS in the issuing of the taxpayer’s compliance status, thus protecting the right to fair administrative action in their dealings with SARS. Taxpayers who are aggrieved by a decision taken by the Revenue Authority are encouraged to timeously address their grievances, commencing with the internal dispute resolution remedies provided for within the TAA. / Taxation

As part of the natural evolution and continued optimisation of their designs, current and future magnetic recording heads, used and proposed in technologies such as perpendicular recording, shingled magnetic recording and two-dimensional magnetic recording, often exhibit asymmetry in their structure. They consist of two semi-infinite poles separated by a gap (where the recording field is produced), with an inner gap faces inclined at an angle. Modelling of the fields from asymmetrical structures is complex, and no explicit solutions are currently available (only implicit conformal mapping solutions are available for rational inclination angles). Moreover, there is limited understanding on the correlation between the gap corner angle and the magnitude, distribution and wavelength response of these head structures. This research was therefore set out to investigate approximate analytical and semi-analytical methods for modelling the magnetic potentials and fields of two-dimensional symmetrical and asymmetrical magnetic recording heads, and deliver a quantitative understanding of the behaviour of the potentials and fields as functions of gap corner angles. The accuracy of the derived expressions (written in terms of the normalised root-mean-square deviation) was assessed by comparison to exact available solutions for limited cases, and to finite-element calculations on Comsol Multiphysics. Two analytical methods were derived to approximately model the fields from two-dimensional heads with tilted gap corners in the presence and absence of a soft magnetic underlayer (SUL): in the first method, the potential near a single, two-dimensional corner held at a constant potential is derived exactly through solution of Laplace's equation for the scalar potential in polar coordinates. Then through appropriate choice of enclosing boundary conditions, the potentials and fields of two corners at equal and opposite potentials and displaced from each other by a distance equal to the gap length were superposed to map the potential and field for asymmetrical and symmetrical heads. For asymmetrical heads, the superposition approximation provided good agreement to finite-element calculations for the limited range of exterior corner angles 0 from 0 (right-angled corner) to 45, due to the mismatch of surface charge densities on both poles for this geometry. For symmetrical head structures, the superposition approximation was found to yield remarkable agreement to exact solutions for all gap corner orientations from 0 (right-angled head) to 90 ("thin" gap head). In the second method derived in this research for modelling asymmetrical heads involved using a rational function approximation with free parameters to model the surface potential of asymmetrical heads. The free parameters and their functional dependence on corner angle were determined through fitting to finite-element calculations, enabling the derivation of analytical expressions for the magnetic fields that are in good agreement with exact solutions for all corner angels (0 to 90). To complement the two approximate methods for modelling the fields from asymmetrical and symmetrical heads, a new general approach based on the sine integral transform was derived to model the reaction of soft underlayers on the surface potential or field of any two-dimensional head structure, for sufficiently close head-to-underlayer separations. This method produces an infinite series of correction terms whose coefficients are functions of the head-to-underlayer separation and gap corner angle, that are added to the surface potential or field in the absence of an underlayer. This new approach demonstrated good agreement with finite-element calculations for sufficiently close head-to-underlayer separations, and with the classical Green's functions solutions for increasing separations. Using the derived analytical method and explicit expressions in this work, an understanding of the nature of the magnetic fields and their spectra as functions of the gap corner angles is gained. This understanding and analytical theory will benefit the modelling, design and optimisation of high performance magnetic recording heads.

Submitted by Fernando Luiz de Vasconcellos Quintella (fquintella290@gmail.com) on 2014-12-19T18:03:40Z No. of bitstreams: 1 Dissertação Mestrado - Final FQ.pdf: 2930502 bytes, checksum: c1930d59919d847b584f24e3105bd6d4 (MD5) / Approved for entry into archive by ÁUREA CORRÊA DA FONSECA CORRÊA DA FONSECA (aurea.fonseca@fgv.br) on 2014-12-22T11:56:08Z (GMT) No. of bitstreams: 1 Dissertação Mestrado - Final FQ.pdf: 2930502 bytes, checksum: c1930d59919d847b584f24e3105bd6d4 (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-01-13T12:07:13Z (GMT) No. of bitstreams: 1 Dissertação Mestrado - Final FQ.pdf: 2930502 bytes, checksum: c1930d59919d847b584f24e3105bd6d4 (MD5) / Made available in DSpace on 2015-01-13T12:07:50Z (GMT). No. of bitstreams: 1 Dissertação Mestrado - Final FQ.pdf: 2930502 bytes, checksum: c1930d59919d847b584f24e3105bd6d4 (MD5) Previous issue date: 2014-04-30 / As questões ligadas às desonerações tributárias como fomento ao desenvolvimento do país vêm ganhando muita importância e destaque no cenário político e econômico brasileiro. Sendo assim, este estudo de caso fictício tem como objetivo promover uma reflexão acerca dos fatores que sejam relevantes para a desoneração da cadeia produtiva do pescado e atingir objetivos educacionais expondo aos estudantes às interdependências e consequências ao longo do processo. O caso também pretende promover uma discussão sobre as ações gerenciais apropriadas, com utilização de ferramentas de planejamento para orientar tomadas de decisões e, para tanto, apresenta alguns fatores facilitadores e obstáculos, bem como benefícios alcançados, que são impactados por múltiplos fatores. Dentro dos parâmetros estabelecidos, as conclusões levam ao entendimento de que a solução mais indicada seria a de trabalhar na desoneração e mais especificamente nas rações do pescado, que, com a redução dos custos, proporcionaria mais demanda, maior produção, mais investimentos em tecnologia, mais formalização da economia e tantos outros benefícios econômicos e sociais.