Nesta dissertação são apresentados os resultados obtidos da espectroscopia de campo integral da nebulosa do Homúnculo. As observações foram feitas na banda J, no intervalo de 10620 Å até 12960 Å, utilizando o IFU (Integral Field Unit) do espectrógrafo CIRPASS (Cambridge Infrared Panoramic Survey Spectrograph), que possui 499 lentes hexagonais. A amostragem espacial é de 0,25"/lente e a resolução espectral, R=3200. A linha do [Fe II] λ12567 permitiu a identificação de duas estruturas no lóbulo NW que ainda não haviam sido relatadas. Através da tomografia Doppler, essas estruturas indicaram a existência de uma região de baixa densidade localizada no lóbulo NW e que não é visível nas imagens feitas na região óptica. Além disso, o Pequeno Homúnculo também foi identificado através do mapeamento das componentes e também nos mapas de velocidade da linha do [Fe II] λ12567. As regiões polares da nebulosa do Homúnculo (onde ocorre a colisão mais intensa entre o vento da fonte central e a região interna dos lóbulos) são mais opacas do que as paredes dos mesmos. Isso é verificado pela diminuição na intensidade da linha do [Fe II] λ12567 no lóbulo SE e pelo aumento desta na linha de visada do lóbulo NW. O disco equatorial foi observado nas linhas da série do H (Paβ e Paγ) e na linha do He I λ10830 como uma componente devido à emissões intrínsecas até distâncias superiores às dimensões aparentes do disco que é observado nas imagens feitas na faixa óptica. A linha do [Fe II] λ12567 também apresenta uma componente associada ao disco equatorial. Regiões de baixa densidade localizadas no toro que envolve a fonte central permitem que a radiação ultravioleta escape e excite o gás contido no disco equatorial. O melhor exemplo desse efeito foi detectado pela tomografia Doppler da linha do He I λ10830, que revelou uma componente de emissão intrínseca que atinge distâncias superiores à borda aparente do lóbulo NW do Homúnculo, e que foi completamente mapeada pela primeira vez nesta dissertação. / The Homunculus nebula was mapped using the integral field technique and the results are presented in this dissertation. The observations were obtained in the J band in the range from 10620 Å to 12960 Å using the CIRPASS's IFU, which contains 499 hexagonal lenses. The spatial sampling is 0,25"/lens and the spectral resolution, set to R=3200. The [Fe II] λ12567 line allowed the identification of two structures in the NW lobe that had not been reported yet. Doppler tomography of this structures revealed a low density region placed in the NW lobe that is not seen in the optical images. Besides, the Little Homunculus was also detected both in the mapping of components of the [Fe II] λ12567 and in its velocity maps. In the Homunculus nebula, the polar regions (where the shock between the stellar bipolar wind and the internal wall of the lobes is stronger) are more opaque than the lobe walls. This can be verified by the decrease in the intensity of the [Fe II] λ12567 in the SE lobe and the enhancement of this line emission in the NW lobe. Emissions due to the equatorial disc were detected both in the H series (Paβ and Paγ) and the He I λ10830 as an intrinsic component up to distances greater than the aparent dimensions of the disc seen in the images taken in the optical range. The [Fe II] λ12567 also presents the component due to the equatorial emission. Low density regions in the torus involving the central source allow a beam of radiation to escape to large radii and thereby excite the gas contained in the equatorial disc. The best example of this effect was detected in the Doppler tomography of the He I λ10830 line, that revealed an intrinsic emission component which reaches distances larger than the aparent boundary of the NW lobe and was firstly mapped in this dissertation.

Nesta dissertação são apresentados os resultados obtidos da espectroscopia de campo integral da nebulosa do Homúnculo. As observações foram feitas na banda J, no intervalo de 10620 Å até 12960 Å, utilizando o IFU (Integral Field Unit) do espectrógrafo CIRPASS (Cambridge Infrared Panoramic Survey Spectrograph), que possui 499 lentes hexagonais. A amostragem espacial é de 0,25"/lente e a resolução espectral, R=3200. A linha do [Fe II] λ12567 permitiu a identificação de duas estruturas no lóbulo NW que ainda não haviam sido relatadas. Através da tomografia Doppler, essas estruturas indicaram a existência de uma região de baixa densidade localizada no lóbulo NW e que não é visível nas imagens feitas na região óptica. Além disso, o Pequeno Homúnculo também foi identificado através do mapeamento das componentes e também nos mapas de velocidade da linha do [Fe II] λ12567. As regiões polares da nebulosa do Homúnculo (onde ocorre a colisão mais intensa entre o vento da fonte central e a região interna dos lóbulos) são mais opacas do que as paredes dos mesmos. Isso é verificado pela diminuição na intensidade da linha do [Fe II] λ12567 no lóbulo SE e pelo aumento desta na linha de visada do lóbulo NW. O disco equatorial foi observado nas linhas da série do H (Paβ e Paγ) e na linha do He I λ10830 como uma componente devido à emissões intrínsecas até distâncias superiores às dimensões aparentes do disco que é observado nas imagens feitas na faixa óptica. A linha do [Fe II] λ12567 também apresenta uma componente associada ao disco equatorial. Regiões de baixa densidade localizadas no toro que envolve a fonte central permitem que a radiação ultravioleta escape e excite o gás contido no disco equatorial. O melhor exemplo desse efeito foi detectado pela tomografia Doppler da linha do He I λ10830, que revelou uma componente de emissão intrínseca que atinge distâncias superiores à borda aparente do lóbulo NW do Homúnculo, e que foi completamente mapeada pela primeira vez nesta dissertação. / The Homunculus nebula was mapped using the integral field technique and the results are presented in this dissertation. The observations were obtained in the J band in the range from 10620 Å to 12960 Å using the CIRPASS's IFU, which contains 499 hexagonal lenses. The spatial sampling is 0,25"/lens and the spectral resolution, set to R=3200. The [Fe II] λ12567 line allowed the identification of two structures in the NW lobe that had not been reported yet. Doppler tomography of this structures revealed a low density region placed in the NW lobe that is not seen in the optical images. Besides, the Little Homunculus was also detected both in the mapping of components of the [Fe II] λ12567 and in its velocity maps. In the Homunculus nebula, the polar regions (where the shock between the stellar bipolar wind and the internal wall of the lobes is stronger) are more opaque than the lobe walls. This can be verified by the decrease in the intensity of the [Fe II] λ12567 in the SE lobe and the enhancement of this line emission in the NW lobe. Emissions due to the equatorial disc were detected both in the H series (Paβ and Paγ) and the He I λ10830 as an intrinsic component up to distances greater than the aparent dimensions of the disc seen in the images taken in the optical range. The [Fe II] λ12567 also presents the component due to the equatorial emission. Low density regions in the torus involving the central source allow a beam of radiation to escape to large radii and thereby excite the gas contained in the equatorial disc. The best example of this effect was detected in the Doppler tomography of the He I λ10830 line, that revealed an intrinsic emission component which reaches distances larger than the aparent boundary of the NW lobe and was firstly mapped in this dissertation.

Lagos bat virus (LBV) belongs to genotype (gt) 2 of the lyssavirus genus in the family Rhabdoviridae, order Mononegavirales. This virus causes fatal rabies encephalitis in vertebrate animals and has only been reported from the African continent except for an imported case from African origin identified in France. The prototype lyssavirus is in fact rabies virus (gt 1) for which a variety of different vaccines are commercially available. These vaccines, however, do not provide protection against the gt 2 viruses. Genotype 2 viruses have not been well studied to date and the true risk for humans and animals is uncertain. The aim of this study was to investigate the epidemiology and pathogenicity of this uniquely African virus. In this project, our surveillance in South Africa reported six new LBV cases after this virus was not reported for the previous 12 years prior to this study. These results indicated that the incidence of this virus is greatly underestimated due to lack or absence of surveillance or ineffective diagnostic abilities of laboratories in Africa. Molecular epidemiological analysis of previously identified and new gt 2 isolates from this study indicated a high intragenotypic nucleotide and amino acid sequence diversity with respect to the Nucleo-, Phospho-, Matrix- and Glycoprotein genes. Based on these analyses, it has been proposed that two virus isolates that were previously reported as gt 2 LBV, may in fact constitute a new lyssavirus genotype. These findings emphasize the need to investigate different criteria for lyssavirus classification. As more lyssaviruses are discovered and with rapid progress in full genome sequencing, diversity becomes accentuated and challenges the criteria upon which lyssavirus taxonomy is based. As a compliment to these genetic findings, our study of viral pathogenicity in a murine model, identified that the pathogenicity of phylogroup II viruses has previously been underestimated. LBV poses a potential risk to humans and animals and future vaccine strategies should ideally include protection against phylogroup II viruses. / Thesis (PhD)--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted

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Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-06-01T13:10:52Z No. of bitstreams: 1 Maria Suelí Periotto.pdf: 4173643 bytes, checksum: 05c709c6d8c6d91874c142a6a65d3141 (MD5) / Made available in DSpace on 2017-06-01T13:10:52Z (GMT). No. of bitstreams: 1 Maria Suelí Periotto.pdf: 4173643 bytes, checksum: 05c709c6d8c6d91874c142a6a65d3141 (MD5) Previous issue date: 2017-05-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This research aims at discussing scientifically and methodologically the teaching practice of the Legion of Good Will (LGW). The LGW applies in its schools located in the Brazilian cities of Belém/PA, Curitiba/PR, Taguatinga/DF, Rio de Janeiro/RJ and São Paulo/SP, and also in Buenos Aires/Argentina, Asunción/Paraguay and Montevideo/Uruguay, a complementary program for the curricular matrix with thematic axles of spirituality. It considers that the individuals‘ scientific knowledge and subjectivity may walk side-by-side taking into account the wholeness of the students, in such a way that the academic initiatives do not limit themselves to a systematic replication of the contents historically organized in the curricula. However, may the academic activities mobilize the students to understand the heritage left by past generations, with their life stories, motivating them to reflect upon what legacy do they intend on leaving for the future, as a new generation. The teaching practice researched considers that all areas of knowledge have convergent points and, based on this principle, some questions appear, as for example: How can the teachers target their practices to meet the curricular requirements of Basic Education, in its different investigation perspectives, and still stimulate the exchange of knowledge, the collaborative interpersonal experience between students and teachers? By doing so, how can they contribute to the humanization of the learning environment and guarantee the intellectual success of the students, as well as their emotional maturity and social empowerment? Does the proposal of the LGW of analyzing the curriculum demand a profound look upon the issues of interdisciplinarity? The school here researched considers appropriate the mediation between the curriculum content and the discussions in society, so that the social, ethical, political, and philosophical implications may awaken the students to a broader look upon things, free from preconceptions. The methodology used in the research was based on the premises of participant observation, explained by Pedro Demo and Carlos Rodrigues Brandão. Its main instrument is the systematic analysis of the school environment on its daily basis activities, recording and examining the data, and elaborating institutional documents that point to information related to the system, space, and time of its occurrence. The theoretical revision of this thesis is based on the interdisciplinarity studies of Ivani Catarina Arantes Fazenda; José Gimeno Sacristán and Pedro Demo contribute with their studies on curriculum; José de Paiva Netto‘s concepts are the basis of the teaching practice of the LGW / Esta pesquisa busca discutir científica e metodologicamente a prática pedagógica da Legião da Boa Vontade (LBV), que aplica em suas escolas de Belém/PA, Curitiba/PR, Taguatinga/DF, Rio de Janeiro/RJ, São Paulo/SP, Buenos Aires/Argentina, Assunção/Paraguai e Montevidéu/Uruguai um programa de complementação da matriz curricular com eixos temáticos de espiritualidade, por considerar que o saber científico e a subjetividade dos indivíduos possam caminhar juntos, ao levar em conta a integralidade dos educandos, de modo que as iniciativas acadêmicas não se limitem à reprodução sistemática de conteúdos historicamente organizados nos currículos, mas que mobilizem os estudantes a apreenderem a herança das gerações anteriores, com suas histórias de vida, motivando-os a fomentar reflexões acerca do legado que pretendem, como geração nova, deixar para o futuro. A prática pedagógica pesquisada considera que todas as áreas do saber possuem pontos convergentes e, desse princípio, questionamentos surgem: Como os professores podem direcionar suas práticas para atender as exigências do currículo da Educação Básica, em suas diferentes perspectivas de investigação, e ainda incentivar a troca de conhecimento, o convívio interpessoal colaborativo entre estudantes e educadores, contribuir para a humanização do ambiente escolar e garantir o êxito intelectual dos alunos, seu amadurecimento emocional e empoderamento social? A forma proposta pela LBV de apreciar o currículo demanda um olhar profundo para as questões da Interdisciplinaridade? A instituição escolar investigada considera pertinente a mediação do conteúdo curricular com as discussões da sociedade, de modo que as implicações sociais, éticas, políticas e filosóficas possam despertar nos alunos um olhar ampliado e isento de preconceitos. A metodologia aplicada na pesquisa pauta-se em premissas da Pesquisa Participante, conceituada por Pedro Demo e Carlos Rodrigues Brandão, tendo como instrumento a observação sistemática do ambiente em sua ocorrência diária, registro e análise, elaborando documentos institucionais que direcionam as informações relativas ao sistema, espaço e tempo de sua aplicação. A revisão teórica desta tese baseia-se nos estudos de Interdisciplinaridade de Ivani Catarina Arantes Fazenda; José Gimeno Sacristán e Pedro Demo trazem subsídios acerca do currículo; e José de Paiva Netto embasa a pratica pedagógica da LBV

Les glycoprotéines de fusion virales de classe 1 contrôlent la fusion entre lenveloppe virale et la membrane cellulaire. Ces glycoprotéines présentent une extrémité N-terminale indispensable à la fusion, le peptide de fusion. Les peptides de fusion sont capables dinduire à eux seuls la fusion de membranes in vitro. Dans cette étude, nous avons dabord analysé les peptides de fusion de gp41 du HIV et de gp30 du BLV. Ces deux peptides de fusion sont des peptides obliques : ils sinsèrent obliquement dans la membrane sous forme hélicoïdale. Nos études ont montré une relation entre la capacité de ces deux peptides de fusion à sinsérer obliquement dans la membrane et la capacité de leurs glycoprotéines de fusion à induire la fusion. Dans le cas du BLV, nous avons également montré une relation entre lobliquité du peptide de fusion et sa fusogénicité. Cette relation obliquité-fusogénicité a été utilisée pour prédire avec succès la région minimale des deux peptides de fusion suffisante pour induire une fusion significative in vitro, qui correspond respectivement aux douze et aux quinze premiers acides aminés de gp41 et gp30. Nos résultats montrent également que le peptide caméléon, un peptide de novo avec une structure labile, sinsère obliquement dans la membrane et induit la fusion in vitro. Le fait que ce peptide fasse partie des peptides obliques, comme les peptides de fusion du HIV et BLV, renforce lhypothèse dun lien entre la fusogénicité des peptides de fusion et leur flexibilité structurale. De nombreuses études réalisées sur les glycoprotéines de fusion de classe 1 indiquent que le domaine transmembranaire intervient également dans la fusion virale. Ce domaine doit être suffisamment long pour que la fusion soit complète. Dans ce travail, nous avons montré quun peptide transmembranaire modèle, le peptide KALR, est capable de sinsérer et dinduire la fusion de liposomes in vitro. En comparant les résultats de modélisation moléculaire avec ceux de FTIR et ceux de la fusion de phase lipidique/perméabilisation de liposomes, nous avons également montré que le taux dinsertion membranaire et la fusogénicité de KALR dépendent de la longueur de son cur hydrophobe. En effet, le taux dinsertion de KALR dans la membrane est beaucoup plus important lorsquil contient un cur hydrophobe lui permettant de traverser entièrement la membrane. Dans cette situation, KALR est capable dinduire la déstabilisation et la fusion de membranes alors que lorsque son cur hydrophobe est trop court pour lui permettre de traverser la membrane, il en est incapable. Ces résultats ont permis dapporter des éléments de compréhension des mécanismes intervenant lors de la fusion induite par les glycoprotéines de fusion virales. / Abstract: Class 1 fusion glycoproteins of viruses are involved in the fusion between viral envelope and cell membrane. The N-terminal extremity of these glycoproteins, called fusion peptide, is essential for fusion. Fusion peptides are able to induce by themselves in vitro membrane fusion. Firstly, we analysed fusion peptides of HIV-1 gp41 and BLV gp30. These two peptides are tilted peptides: they insert obliquely in the membrane when helical. Our studies showed a correlation between the ability of these two fusion peptides to insert obliquely in the membrane and the ability of whole glycoproteins to induce fusion. For BLV, a relationship between the obliquity of the fusion peptide and its fusogenicity was also observed. This obliquity/fusogenicity relationship was used to successfully predict the minimal region of the two fusion peptides sufficient to induce significant in vitro fusion. The minimal fusion peptide corresponds respectively to the twelve and to the fifteen first residues of gp41 and gp30. Our results also showed that the chameleon peptide, a de novo peptide with structural flexibility, inserts obliquely into the membrane and induces in vitro fusion. The fact that this peptide is a tilted peptide, like fusion peptides of HIV-1 and BLV, confirms the hypothesis of a relationship between the fusion peptides fusogenicity and their structural flexibility. A lot of studies on class 1 fusion glycoproteins of viruses indicate that the transmembrane domain is also directly involved in the viral fusion. Glycoproteins must have a domain long enough to induce complete fusion. In this study, we showed that a model transmembrane peptide, KALR peptide, is able to insert into membranes and to induce their fusion. By comparing molecular modelling results with those of FTIR, of liposomes lipid-mixing and of liposomes leakage, we also showed that the insertion rate into the membranes and the fusogenicity of KALR depend on the length of its hydrophobic core. Indeed, the insertion rate of KALR into the membrane is greatly larger when it contains a hydrophobic core long enough to allow the peptide to traverse the membrane. In this situation, KALR is able to destabilize membranes and to induce their fusion, while when it is too short to match the membrane, it is unable to induce fusion. These results allow to better understanding mechanisms involved in the fusion induced by viral fusion glycoproteins.