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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigation of PEPPSI precatalysts for controlled polymerization of -conjugated polymers from cheap starting materials

Groombridge, Benjamin John January 2015 (has links)
Since the discovery of catalyst-transfer polymerization in 2004 there has been significant research into expanding the scope from Kumada couplings of poly-thiophenes mediated by nickel initiators. This thesis presents an investigation toward the synthesis of -conjugated polymers by the elusive pseudo-living polymerization of chloroarene monomers. Chapter 1 sets the scene with an in-depth review of chain-growth polymerizations mediated by palladium catalysts. In chapter 2, we report the first examples of exhaustive substitution of poly-chloroarenes in the presence of a deficit of nucleophile in the sp3-sp2 Negishi coupling mediated by PEPPSI-IPr. These experiments demonstrated intramolecular transfer of the active catalyst which is essential for catalyst-transfer polymerization. Chapter 3 describes the synthesis of the highly active PEPPSI-IPent precatalyst from cheap commercially available starting materials with minimal purification. Subsequently in chapter 4, it was demonstrated that PEPPSI-IPent undergoes exhaustive substitution of poly-chloroarenes in the presence of a deficit of nucleophile in sp2-sp2 Kumada, Negishi and Suzuki cross-couplings. In chapter 5, optimization of current Kumada polymerization of bromo phenylene-based monomer mediated by PEPPSI-IPr is described. Direct comparison of model reactions and Kumada polycondensation confirmed high selectivity for exhaustive substitution is required to achieve polycondensation in a chain-growth manner. Initial research into catalyst-transfer polycondensation of chloroarene monomers did not achieve polymerization in a chain-growth manner using modified conditions from bromoarene monomers.
2

The development of small-molecule sensors using a modular CuAAC approach

Jobe, Kajally January 2014 (has links)
Due to the fundamental roles sensors play in the study of biological, chemical and environmental processes, considerable efforts have been directed towards the synthesis of robust systems capable of detecting a wide range of analytes with high selectivity and sensitivity over a range of analyte concentrations. This thesis presents an investigation into the design and synthesis of novel 'click' generated chemo- and bio-sensors and molecular machines for fluorescence sensing applications in vitro and in vivo. The introductory chapter highlights recent and relevant examples of 'click'-derived chemosensors that use charge and energy transfer processes as transduction mechanisms for analyte detection. The synthesis and application of fluorescence- based Zn(II) sensors prepared using 'click' chemistry is then described. These sensors have proven to be effective tools for the selective detection of Zn(II) in vitro and in vivo and are synthetically simple to prepare using modular routes. The third chapter describes the synthesis of a series of novel fluorescent [2]rotaxanes which display cation sensing properties, with extremely varied photo-physical properties resulting from small structural changes. A novel approach to bio-sensing is then introduced, based on an 'allosteric scorpionate' model. In these systems, electron paramagnetic resonance (EPR) spectroscopy is used to detect the remote interaction between 'click'-generated Cu(II)-azamacrocyclic complexes containing biotinylated pendant arms and their biological target.
3

Detection and quantification of caffeine in the coffee industry using imprinted polymers and bare carbon electrodes

Redivo, Luca January 2018 (has links)
Food quality control is a mandatory task in the food industry, and for coffee manufacturers, one of the key target compounds is caffeine, because of its well-known biological effects and currently expensive analytical methods are employed for caffeine quantification. This project was thought with the aim of developing a cost-effective caffeine sensor for application in industrial environments. Two main approaches were investigated: i) the use of imprinted polymers; ii) electrochemical using bare carbon electrodes. Chapter 1 is the main introduction, it focuses on the importance of food quality control, the limitation of the methodologies currently employed and it presents the advantages of using imprinted polymers recognition and electrochemistry signal transduction. Chapter 2 presents data related to studies of self-association of caffeine in water using a novel computational approach. The wider applicability of the method was assessed by studying self-association of paraxanthine and the results were validated via a collaboration with Miss R. Anastasiadi who employed isothermal titration calorimetry. Chapter 3 describes the synthesis of MIPs in water, starting with the selection of the functional monomers: HPTS (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt). The polymerisation conditions were optimised in terms of solvent to be used, initiator content, temperature and total monomer concentration. Afterwards, the polymers were synthesised, characterised, and preliminary data on the rebinding ability towards caffeine were presented. Chapter 4 focuses on electrochemical methods for the detection of caffeine using bare carbon electrodes. A voltammetric method for accurate determination of caffeine in beverages was developed. Based on the encouraging results obtained, further studies on the applicability of electrochemical methods for coffee quality analysis were done. A second method was developed for simultaneous detection of caffeine and polyphenols and an amperometric chemosensor for sucrose determination was acquired and its applicability for the analysis of green coffee beans was evaluated.
4

Ensino de química : a inclusão de discentes surdos e os aspectos do processo de ensino-aprendizagem

Machado, Raquel Brusco January 2016 (has links)
A inclusão de estudantes surdos nas escolas da rede pública estadual, prevista em legislação, está crescendo e dando origem a um novo cenário educacional. A presença de tradutor/intérprete de Língua Brasileira de Sinais nas salas de aula, para auxiliar na comunicação do estudante surdo com seus professores e com os demais colegas da turma é um aspecto visível de transformação. No entanto, o que precisa ser compreendido é que o intérprete atua como intermediário no processo de ensino e aprendizagem e que, a sua presença por si só, não garante o processo de inclusão e de aprendizagem dos surdos. Isso porque a educação inclusiva é complexa e relativa, dependendo muito da atuação ética dos profissionais envolvidos com a realidade escolar e do grau de alfabetização dos surdos em LIBRAS e na escrita da Língua Portuguesa. Ter um estudante surdo no Ensino Médio Politécnico e, de imediato, poder contar com um intérprete favorece a inclusão e facilita o contato com as disciplinas. Mas quando se trata da disciplina de química, considerada abstrata e de difícil entendimento pela maioria dos estudantes de ensino médio, como o estudante surdo, o intérprete e o professor necessitam agir para conseguir dar conta da inclusão e da aprendizagem da Ciência Química, ambas complexas e distantes Essa realidade escolar experienciada pela professora-pesquisadora deste estudo instigou uma mudança de atuação docente em prol de investigações sobre a constituição do sujeito surdo, da Língua Brasileira de Sinais, do profissional intérprete de LIBRAS e, a mais importante delas, como desenvolver um ensino de química para estudantes surdos de uma maneira que despertasse o interesse dos mesmos em aprendê-la. Missão essa desafiadora e, ao mesmo tempo, propulsora de uma pesquisa de pós-graduação em nível de mestrado, a qual buscou entender e refletir um pouco mais sobre a vivência diária na educação básica. Diante disso, adotou-se a metodologia de pesquisa bibliográfica com o intuito de conhecer aspectos da cultura e da identidade surda, da Língua Brasileira de Sinais e das legislações que norteiam a educação inclusiva para entender como ocorre a inserção do sujeito surdo nas escolas da rede pública estadual. Também, utilizando uma adaptação da proposta de situação de estudo, elaborou-se um projeto de pesquisa com atividades práticas que visam relacionar conceitos químicos com o cotidiano dos estudantes surdos. Para desenvolver essa metodologia escolheu-se a temática da adulteração do leite, situação problema presente na comunidade escolar investigada e rica em conceitos químicos. / The inclusion of deaf students in state public schools, foreseen in law, is growing and giving rise to a new educational scene. The presence of a translator/interpreter of Brazilian Sign Language in the classroom to assist in communication of the deaf students with their teachers and with other classmates is a visible aspect of transformation. However, what needs to be understood is that the interpreter acts as an intermediary in the process of teaching and learning and that his presence alone doesn‟t guarantee the inclusion process and learning of deaf students. This is because the inclusive education is complex and relative, depending largely on ethical performance of professionals involved with the school reality and level of literacy of the deaf in LIBRAS and writing of the Portuguese language. Having a deaf student at the Polytechnic High School and, immediately, able to rely on an interpreter promotes the inclusion and facilitates contact with the subjects. But when it is the subject of Chemistry, considered abstract and hard to understand by most of high school students, how the deaf student, the interpreter and the teacher need to act to get to realize the inclusion and Chemical Science learning, both complex and distant This school reality, experienced by the teacherresearcher of this study, instigate a change in teaching practice for the benefit of investigations of the constitution of the deaf person, the Brazilian Sign Language, the LIBRAS professional interpreter and, the most important of them, how to develop a teaching chemistry for deaf students in a way that arouses the interest of the same in learning it. This mission is challenging and the same time, driving a post-graduate research at the master's level, which aimed to understand and reflect a little more about the daily life in basic education. Therefore, we adopted the bibliographical research methodology in order to know aspects of culture and deaf identity, the Brazilian Sign Language and of the laws that guide inclusive education to understand how the insertion of the deaf subject occurs in the state public schools. Also, using an adaptation of the proposed study situation, a research project was created with practical activities that aim at relating chemical concepts to the daily lives of deaf students. To develop this methodology was chosen the theme of milk adulteration, this problem situation in the school community investigated and rich in chemical concepts. To develop this methodology was chosen the theme of milk adulteration, present problem situation in the school community investigated and rich in chemical concepts.
5

Ensino de química : a inclusão de discentes surdos e os aspectos do processo de ensino-aprendizagem

Machado, Raquel Brusco January 2016 (has links)
A inclusão de estudantes surdos nas escolas da rede pública estadual, prevista em legislação, está crescendo e dando origem a um novo cenário educacional. A presença de tradutor/intérprete de Língua Brasileira de Sinais nas salas de aula, para auxiliar na comunicação do estudante surdo com seus professores e com os demais colegas da turma é um aspecto visível de transformação. No entanto, o que precisa ser compreendido é que o intérprete atua como intermediário no processo de ensino e aprendizagem e que, a sua presença por si só, não garante o processo de inclusão e de aprendizagem dos surdos. Isso porque a educação inclusiva é complexa e relativa, dependendo muito da atuação ética dos profissionais envolvidos com a realidade escolar e do grau de alfabetização dos surdos em LIBRAS e na escrita da Língua Portuguesa. Ter um estudante surdo no Ensino Médio Politécnico e, de imediato, poder contar com um intérprete favorece a inclusão e facilita o contato com as disciplinas. Mas quando se trata da disciplina de química, considerada abstrata e de difícil entendimento pela maioria dos estudantes de ensino médio, como o estudante surdo, o intérprete e o professor necessitam agir para conseguir dar conta da inclusão e da aprendizagem da Ciência Química, ambas complexas e distantes Essa realidade escolar experienciada pela professora-pesquisadora deste estudo instigou uma mudança de atuação docente em prol de investigações sobre a constituição do sujeito surdo, da Língua Brasileira de Sinais, do profissional intérprete de LIBRAS e, a mais importante delas, como desenvolver um ensino de química para estudantes surdos de uma maneira que despertasse o interesse dos mesmos em aprendê-la. Missão essa desafiadora e, ao mesmo tempo, propulsora de uma pesquisa de pós-graduação em nível de mestrado, a qual buscou entender e refletir um pouco mais sobre a vivência diária na educação básica. Diante disso, adotou-se a metodologia de pesquisa bibliográfica com o intuito de conhecer aspectos da cultura e da identidade surda, da Língua Brasileira de Sinais e das legislações que norteiam a educação inclusiva para entender como ocorre a inserção do sujeito surdo nas escolas da rede pública estadual. Também, utilizando uma adaptação da proposta de situação de estudo, elaborou-se um projeto de pesquisa com atividades práticas que visam relacionar conceitos químicos com o cotidiano dos estudantes surdos. Para desenvolver essa metodologia escolheu-se a temática da adulteração do leite, situação problema presente na comunidade escolar investigada e rica em conceitos químicos. / The inclusion of deaf students in state public schools, foreseen in law, is growing and giving rise to a new educational scene. The presence of a translator/interpreter of Brazilian Sign Language in the classroom to assist in communication of the deaf students with their teachers and with other classmates is a visible aspect of transformation. However, what needs to be understood is that the interpreter acts as an intermediary in the process of teaching and learning and that his presence alone doesn‟t guarantee the inclusion process and learning of deaf students. This is because the inclusive education is complex and relative, depending largely on ethical performance of professionals involved with the school reality and level of literacy of the deaf in LIBRAS and writing of the Portuguese language. Having a deaf student at the Polytechnic High School and, immediately, able to rely on an interpreter promotes the inclusion and facilitates contact with the subjects. But when it is the subject of Chemistry, considered abstract and hard to understand by most of high school students, how the deaf student, the interpreter and the teacher need to act to get to realize the inclusion and Chemical Science learning, both complex and distant This school reality, experienced by the teacherresearcher of this study, instigate a change in teaching practice for the benefit of investigations of the constitution of the deaf person, the Brazilian Sign Language, the LIBRAS professional interpreter and, the most important of them, how to develop a teaching chemistry for deaf students in a way that arouses the interest of the same in learning it. This mission is challenging and the same time, driving a post-graduate research at the master's level, which aimed to understand and reflect a little more about the daily life in basic education. Therefore, we adopted the bibliographical research methodology in order to know aspects of culture and deaf identity, the Brazilian Sign Language and of the laws that guide inclusive education to understand how the insertion of the deaf subject occurs in the state public schools. Also, using an adaptation of the proposed study situation, a research project was created with practical activities that aim at relating chemical concepts to the daily lives of deaf students. To develop this methodology was chosen the theme of milk adulteration, this problem situation in the school community investigated and rich in chemical concepts. To develop this methodology was chosen the theme of milk adulteration, present problem situation in the school community investigated and rich in chemical concepts.
6

Ensino de química : a inclusão de discentes surdos e os aspectos do processo de ensino-aprendizagem

Machado, Raquel Brusco January 2016 (has links)
A inclusão de estudantes surdos nas escolas da rede pública estadual, prevista em legislação, está crescendo e dando origem a um novo cenário educacional. A presença de tradutor/intérprete de Língua Brasileira de Sinais nas salas de aula, para auxiliar na comunicação do estudante surdo com seus professores e com os demais colegas da turma é um aspecto visível de transformação. No entanto, o que precisa ser compreendido é que o intérprete atua como intermediário no processo de ensino e aprendizagem e que, a sua presença por si só, não garante o processo de inclusão e de aprendizagem dos surdos. Isso porque a educação inclusiva é complexa e relativa, dependendo muito da atuação ética dos profissionais envolvidos com a realidade escolar e do grau de alfabetização dos surdos em LIBRAS e na escrita da Língua Portuguesa. Ter um estudante surdo no Ensino Médio Politécnico e, de imediato, poder contar com um intérprete favorece a inclusão e facilita o contato com as disciplinas. Mas quando se trata da disciplina de química, considerada abstrata e de difícil entendimento pela maioria dos estudantes de ensino médio, como o estudante surdo, o intérprete e o professor necessitam agir para conseguir dar conta da inclusão e da aprendizagem da Ciência Química, ambas complexas e distantes Essa realidade escolar experienciada pela professora-pesquisadora deste estudo instigou uma mudança de atuação docente em prol de investigações sobre a constituição do sujeito surdo, da Língua Brasileira de Sinais, do profissional intérprete de LIBRAS e, a mais importante delas, como desenvolver um ensino de química para estudantes surdos de uma maneira que despertasse o interesse dos mesmos em aprendê-la. Missão essa desafiadora e, ao mesmo tempo, propulsora de uma pesquisa de pós-graduação em nível de mestrado, a qual buscou entender e refletir um pouco mais sobre a vivência diária na educação básica. Diante disso, adotou-se a metodologia de pesquisa bibliográfica com o intuito de conhecer aspectos da cultura e da identidade surda, da Língua Brasileira de Sinais e das legislações que norteiam a educação inclusiva para entender como ocorre a inserção do sujeito surdo nas escolas da rede pública estadual. Também, utilizando uma adaptação da proposta de situação de estudo, elaborou-se um projeto de pesquisa com atividades práticas que visam relacionar conceitos químicos com o cotidiano dos estudantes surdos. Para desenvolver essa metodologia escolheu-se a temática da adulteração do leite, situação problema presente na comunidade escolar investigada e rica em conceitos químicos. / The inclusion of deaf students in state public schools, foreseen in law, is growing and giving rise to a new educational scene. The presence of a translator/interpreter of Brazilian Sign Language in the classroom to assist in communication of the deaf students with their teachers and with other classmates is a visible aspect of transformation. However, what needs to be understood is that the interpreter acts as an intermediary in the process of teaching and learning and that his presence alone doesn‟t guarantee the inclusion process and learning of deaf students. This is because the inclusive education is complex and relative, depending largely on ethical performance of professionals involved with the school reality and level of literacy of the deaf in LIBRAS and writing of the Portuguese language. Having a deaf student at the Polytechnic High School and, immediately, able to rely on an interpreter promotes the inclusion and facilitates contact with the subjects. But when it is the subject of Chemistry, considered abstract and hard to understand by most of high school students, how the deaf student, the interpreter and the teacher need to act to get to realize the inclusion and Chemical Science learning, both complex and distant This school reality, experienced by the teacherresearcher of this study, instigate a change in teaching practice for the benefit of investigations of the constitution of the deaf person, the Brazilian Sign Language, the LIBRAS professional interpreter and, the most important of them, how to develop a teaching chemistry for deaf students in a way that arouses the interest of the same in learning it. This mission is challenging and the same time, driving a post-graduate research at the master's level, which aimed to understand and reflect a little more about the daily life in basic education. Therefore, we adopted the bibliographical research methodology in order to know aspects of culture and deaf identity, the Brazilian Sign Language and of the laws that guide inclusive education to understand how the insertion of the deaf subject occurs in the state public schools. Also, using an adaptation of the proposed study situation, a research project was created with practical activities that aim at relating chemical concepts to the daily lives of deaf students. To develop this methodology was chosen the theme of milk adulteration, this problem situation in the school community investigated and rich in chemical concepts. To develop this methodology was chosen the theme of milk adulteration, present problem situation in the school community investigated and rich in chemical concepts.
7

CARREIRA ILUSTRADA, CIÃNCIA QUÃMICA E AÃÃES HIGIENISTAS: A TRAJETÃRIA DE JOSÃ VIEIRA DE FARIA ARAGÃO ATALIBA, PORTUGAL-COIMBRA, BRASIL-SALVADOR (1820-1853) / LLUSTRATED CAREER, SCIENCE AND SHARES HYGIENISTS CHEMISTRY: THE JOURNEY OF JOSÃ DO VIEIRA DE ARAGON AYALIBA, PORTUGAL-Coimbra, BRAZIL-SALVADOR (1820-1853)

Ana LÃcia de Melo Silva 12 September 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente estudo trata do processo de ilustraÃÃo de Josà Vieira de Faria AragÃo Ataliba (1804 â 1853). A escolha pelo referido sujeito deu-se diante da informaÃÃo que o mesmo foi o professor da cadeira de QuÃmica no perÃodo de 1833-1837, na Faculdade de Medicina da Bahia.Nestas circunstÃncias e tendo por base as atividades assumidas por ele, trÃs objetivos foram propostos. O primeiro, conhecer o processo de ilustraÃÃo de Josà Viera de Faria AragÃo Ataliba, em Portugal, situando-o como estudante na Universidade de Coimbra; o segundo, conhecer a formaÃÃo do mencionado sujeito em medicina e as experiÃncias conimbricenses; o terceiro, compreender o seu percurso de atuaÃÃo profissional, identificando a CiÃncia QuÃmica como interface nas suas atividades higienistas. O recorte temporal da pesquisa inicia-se em1820, quando Josà Vieira de Faria AragÃo Ataliba comeÃou seus estudos acadÃmicos na Universidade de Coimbra. O ano de 1853 finaliza o recorte temporal, pois representa o ano de morte do sujeito citado. A investigaÃÃo à resultado de pesquisas em arquivos e bibliotecas das cidades de Salvador, Coimbra e Lisboa, alÃm de leitura de periÃdicos. A tipologia dos registros empÃricos (fragmentados e nÃo seriais) da trajetÃria do sujeito foi constituÃda, essencialmente, por periÃdicos, registros escolares, memÃrias, tratados de higiene e outras informaÃÃes secundÃrias que permitiram compreender como determinados costumes e hÃbitos culturais foram adquiridos pelas instruÃÃes dadas ao sujeito ilustrado do perÃodo. Os vestÃgios encontrados sobre a experiÃncia cultural de Josà Vieira de Faria AragÃo Ataliba nos conduziram Ãs reflexÃes sobre os planos de estudos mÃdicos de 1772 e 1812 da Universidade de Coimbra, aos debates teÃricos sobre o ensino de QuÃmica na mesma instituiÃÃo e ao processo de ilustraÃÃo em Portugal. Por intermÃdio dessas postulaÃÃes, foi possÃvel compreender a postura profissional de Josà Vieira de Faria AragÃo Ataliba ao realizar aÃÃes higienistas, na realidade baiana, ancoradas nos pressupostos quÃmicos. / This study is base don the process of illustration by Josà Vieira de Faria AragÃo Ataliba (1804- 1853). I have made such a choice because this person used to be a chemistry professor at the medical school in Bahia from 1833 to 1837. This way, considering the activitie shehad, I proposed three main goals. First, tok now how his process was developed in Portugal as still a student at the Coimbra University; second, tounder stand his major in general, as well as his experiences in that country and, third, to get to know his path towards this carrer, identifying chemistry as an interface in his hygene activities. This part of theres earch starts back in 1820, when Josà Vieira Ataliba entered the university. It finishes in 1853, due to his death. This investigation is a result of various earches in files and libraries in Salvador, Coimbra and Lisbon, be sides reading lots of news papers. The registers, built essencially through news papers, school record sandh is memoirs, were, unfortunately, fragmented and not cronological. Despite this, all the information all owed us to see how certain cultural habits have been acquired by him. His cultural experience has conducted us to reflect about the medical study plans from 1772 to 1812, the theoretical debates on the chemistry teachin gat that university, and also the illustration process in Portugal. Through all these postulations, it has been possible tounder stant Josà Vieira Atalibaâs professional attitude, when executing hygeneactions in Bahia, based in chemical pretexts.
8

Carreira ilustrada, ciência química e ações higienistas: a trajetória de José Vieira de Faria Aragão Ataliba, Portugal-Coimbra, Brasil-Salvador (1820-1853) / Illustrated career, science and shares hygienists chemistry: the journey of José do Vieira de Aragon ayaliba, Portugal-Coimbra, Brazil-Salvador (1820-1853)

SILVA, Ana Lícia de Melo January 2014 (has links)
SILVA, Ana Lícia de Melo. Carreira ilustrada, ciência química e ações higienistas: a trajetória de José Vieira de Faria Aragão Ataliba, Portugal-Coimbra, Brasil-Salvador (1820-1853). 2014. 124f. – Dissertação (Mestrado) – Universidade Federal do Ceará, Programa de Pós-graduação em Educação Brasileira, Fortaleza (CE), 2014. / Submitted by Márcia Araújo (marcia_m_bezerra@yahoo.com.br) on 2014-09-24T17:10:20Z No. of bitstreams: 1 2014_dis_almsilva.pdf: 1474827 bytes, checksum: 7e36b6dd47dff41daf1e6fec717a297f (MD5) / Approved for entry into archive by Márcia Araújo(marcia_m_bezerra@yahoo.com.br) on 2014-09-25T15:01:19Z (GMT) No. of bitstreams: 1 2014_dis_almsilva.pdf: 1474827 bytes, checksum: 7e36b6dd47dff41daf1e6fec717a297f (MD5) / Made available in DSpace on 2014-09-25T15:01:19Z (GMT). No. of bitstreams: 1 2014_dis_almsilva.pdf: 1474827 bytes, checksum: 7e36b6dd47dff41daf1e6fec717a297f (MD5) Previous issue date: 2014 / This study is base don the process of illustration by José Vieira de Faria Aragão Ataliba (1804- 1853). I have made such a choice because this person used to be a chemistry professor at the medical school in Bahia from 1833 to 1837. This way, considering the activitie shehad, I proposed three main goals. First, tok now how his process was developed in Portugal as still a student at the Coimbra University; second, tounder stand his major in general, as well as his experiences in that country and, third, to get to know his path towards this carrer, identifying chemistry as an interface in his hygene activities. This part of theres earch starts back in 1820, when José Vieira Ataliba entered the university. It finishes in 1853, due to his death. This investigation is a result of various earches in files and libraries in Salvador, Coimbra and Lisbon, be sides reading lots of news papers. The registers, built essencially through news papers, school record sandh is memoirs, were, unfortunately, fragmented and not cronological. Despite this, all the information all owed us to see how certain cultural habits have been acquired by him. His cultural experience has conducted us to reflect about the medical study plans from 1772 to 1812, the theoretical debates on the chemistry teachin gat that university, and also the illustration process in Portugal. Through all these postulations, it has been possible tounder stant José Vieira Ataliba’s professional attitude, when executing hygeneactions in Bahia, based in chemical pretexts. / O presente estudo trata do processo de ilustração de José Vieira de Faria Aragão Ataliba (1804 – 1853). A escolha pelo referido sujeito deu-se diante da informação que o mesmo foi o professor da cadeira de Química no período de 1833-1837, na Faculdade de Medicina da Bahia.Nestas circunstâncias e tendo por base as atividades assumidas por ele, três objetivos foram propostos. O primeiro, conhecer o processo de ilustração de José Viera de Faria Aragão Ataliba, em Portugal, situando-o como estudante na Universidade de Coimbra; o segundo, conhecer a formação do mencionado sujeito em medicina e as experiências conimbricenses; o terceiro, compreender o seu percurso de atuação profissional, identificando a Ciência Química como interface nas suas atividades higienistas. O recorte temporal da pesquisa inicia-se em1820, quando José Vieira de Faria Aragão Ataliba começou seus estudos acadêmicos na Universidade de Coimbra. O ano de 1853 finaliza o recorte temporal, pois representa o ano de morte do sujeito citado. A investigação é resultado de pesquisas em arquivos e bibliotecas das cidades de Salvador, Coimbra e Lisboa, além de leitura de periódicos. A tipologia dos registros empíricos (fragmentados e não seriais) da trajetória do sujeito foi constituída, essencialmente, por periódicos, registros escolares, memórias, tratados de higiene e outras informações secundárias que permitiram compreender como determinados costumes e hábitos culturais foram adquiridos pelas instruções dadas ao sujeito ilustrado do período. Os vestígios encontrados sobre a experiência cultural de José Vieira de Faria Aragão Ataliba nos conduziram às reflexões sobre os planos de estudos médicos de 1772 e 1812 da Universidade de Coimbra, aos debates teóricos sobre o ensino de Química na mesma instituição e ao processo de ilustração em Portugal. Por intermédio dessas postulações, foi possível compreender a postura profissional de José Vieira de Faria Aragão Ataliba ao realizar ações higienistas, na realidade baiana, ancoradas nos pressupostos químicos.
9

Stochastic Models Suggest Guidelines for Protocols with Novel HIV-1 Interventions

Gupta, Vipul January 2017 (has links) (PDF)
The treatment of human immunodeficiency virus (HIV-1) infection faces the challenge of drug resistance. The high mutation rate of HIV-1 allows it to develop resistance against all available drugs. New mechanisms of intervention that do not succumb to failure through resistance are thus being explored. Mutagens that increase the viral mutation rate are a promising class of drugs. They can drive HIV-1 past a critical mutation rate, called the error threshold, and induce a catastrophic loss of genetic information. The treatment duration for a mutagen to drive HIV-1 beyond this error threshold is not yet estimated. We devise a detailed stochastic simulation of HIV-1 infection to estimate this duration. The simulations predict that the required duration is inversely proportional to the difference between the mutation rate induced by a mutagen and the error threshold. This scaling is robust to changes in simulation parameters. Using this scaling, we estimate the required duration of treatment with mutagens to be many years. Unfortunately, all available drugs, including mutagens, fail to clear the infection because HIV-1 establishes a reservoir of latently infected cells harbouring silent HIV-1 integrated genomes. A new \shock and kill" strategy that aims to activate latent cells and render them susceptible to immune killing or viral cytopathicity and thus to eradicate the HIV-1 latent reservoir has been suggested. Several latency reversal agents (LRAs) have been developed. Individual LRAs fail to show any decline in the HIV-1 latent reservoir in clinical trials. Combinations of LRAs have been tested in a few in-vitro and ex-vivo experiments. It has been found that in combination LRAs act synergistically. Finding the drug concentrations that yield the maximum synergy may be helpful in achieving a sterilizing cure. Here, we develop an intracellular model to estimate these drug concentrations. We choose drugs from two different classes of LRAs and show that our model captures quantitatively recent in-vitro experiments of their activity individually and in combination. With this model, we estimate the concentrations of the drugs required to obtain the maximum synergy. Strong CD8+ T cell responses against viruses have been associated with low levels of viremia. Elite controllers of HIV-1, who are known to have low or undetectable viremia, mount a cross-reactive CD8+ T cell response against the pathogen which controls viral mutation-driven escape from immune activity. These cross-reactive responses are against specific epitopes of HIV-1. Our goal was to examine whether such epitopes could be identified systematically so that a cross-reactive immune response could be induced by using these epitopes as immunogens. Immune recognition of an epitope involves two parts: presentation of the epitope, or peptide, by the major histocompatibility complex (MHC) molecules in the host and high a finity binding of the peptide-MHC complex with a T cell receptor (TCR). Immune escape could occur at either of these steps. Here, we examined the first step. We devise the following procedure to identify peptides that sustain HLA binding despite mutations. First, from the full length HIV-1 (HCV) proteome, we identify viral peptides that bind tightly with MHC molecules using the software NetMHCpan2.8. Next, we pick the peptides and their complementary MHC molecules that yield tight binding and mutate the peptides bit by bit to examine whether binding was compromised. We identify several viral peptide-MHC pairs that display tight binding despite all possible single mutations of the peptides both with HIV-1 and HCV. These peptides present candidates which can be tested for their TCR binding and cross-reactive immunogenic potential.

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