Colorectal cancer (CRC) is one of the most common cancer types and leading causes of cancer death worldwide. Since CRC is a heterogenic disease, there is a demand for increased knowledge of the underlying genetic and epigenetic mechanisms. The aim of this thesis was to investigate heredity and potential tumour markers in relation to prognosis. In paper I, survival of patients with CRC and a positive family history of CRC in first-degree relatives was analysed. Patients with colon cancer and positive family history of CRC had improved survival compared to patients with negative family history. This improvement in survival could not be explained by known clinico-pathological factors. In paper II, we investigated the prognostic value of Tryptophanyl t-RNA synthetase (TrpRS) in tissues from patients operated for CRC. Low protein expression of TrpRS in primary tumour tissues correlated with increased risk of recurrence and poorer survival. In paper III, the prognostic value of microsatellite instability (MSI) and the correlation to heredity for CRC in first-degree relatives was investigated. Patients with proximal colon cancer and MSI had improved cancer specific survival. There were no correlation between MSI and heredity. In paper IV, we evaluated the potential use of proximity ligation assay (SP-PLA) in patients with CRC, by simultaneous analysis of 35 proteins in only 5 μl plasma. SP-PLA is a suitable method for protein detection and might give valuable guidance in pursuing new prognostic and predictive tumour markers. However, none of the markers selected for present SP-PLA analyses gave better prognostic information than CEA. In conclusion, heredity is related to better survival independent of MSI in patients with CRC and MSI is associated with better prognosis in proximal colon cancer. Detection and increased knowledge of molecular mechanism in CRC is important, however it needs to be further investigated and validated in clinical use.

The biocompatibility and biodegradability of poly(lactic acid) (PLA) facilitate its use in a variety of biomedical applications, ranging from sutures to drug delivery. However, uncontrolled interactions with cells and insufficient mechanical properties have prevented PLA from reaching its full potential as a scaffold for use in tissue engineering. Methods to improve the mechanical, chemical and biological properties of PLA are limited by the lack of functional groups along the backbone of the polymer. One possible approach towards overcoming these limitations involves the incorporation of functional groups into the backbone of the polymer through the copolymerization of monomers bearing protected functional groups. Deprotection and modification of these functional groups could provide the opportunity to direct the attachment of cells, and enhance to the physical properties of the polymer. We have developed a general methodology for the synthesis of lactide monomers substituted with protected functional groups (alcohols protected as benzyl ethers, amines protected as benzyl carbamates and carboxylic acids protected as benzyl esters). The monomers were homopolymerized, and copolymerized with lactide, and deprotected to give functional PLA copolymers with pendant hydroxyl, amine, and carboxyl groups. A thorough investigation of the chemical modification of PLA copolymers bearing functional groups along the polymer backbone was performed on a copolymer prepared by copolymerizarion of a dibenzyloxy-substituted lactide monomer with lactide followed by reductive debenzylation. Reaction of the resulting hydroxyl-substited PLA with succinic anhydride resulted in an acid-substituted PLA that is amenable to standard EDC/NHS coupling. The utility of this copolymer was illustrated by coupling with an amine derivative of biotin, and an RGD-containing peptide sequence. The preparation of the biodegradable polyester substituted with RGD, a ubiquitous adhesion peptide, provided us with control over cellular attachment to the hybrid material. We also explored approaches to make use of the pendant functional groups on PLA to enhance the physical properties of polymer foams. Copolymers with pendant photocrosslinkable cinnamate groups were prepared by reaction of the hydroxyl-substited PLA copolymers with cinnamoyl chloride. The copolymer was foamed using thermally-induced phase separation (TIPS), and photocrosslinked upon irradiation at 300 nm. Irradiation resulted in an increase in the compressive modulus of the foams. Crosslinking also led to a decrease in the rate of hydrolytic degradation of the foams, thereby demonstrating the potential for use of these strategies in the development of porous scaffolds for bioengineering. Another potential approach towards the preparation of robust polymer foams is the incorporation of a rigid polymer block which can phase separate during foam formation to provide additional structural integrity. Several poly(norbornene)-PLA diblock copolymer compositions were prepared by the ring-opening of lactide by a hydroxyl-terminated poly(norbornene) macroinitiator. The ability of the diblock copolymer to phase separate at elevated temperature was verified using small-angle x-ray scattering and wide-angle x-ray scattering.

Poly(lactic acid), PLA, is a viable replacement to petroleum derived polymers due to its renewable feedstock, biodegradability and bioassimilability, yet improvements in its physical, thermal and mechanical properties are required before it can fully enter all commodity markets. This thesis investigates olefin cross-metathesis (CM) as a synthetic strategy to modify the properties of PLA. The use of novel lanthanide and actinide catalysts on the microstructure control of PLA are also explored. The Tebbe reagent was used in a new synthetic strategy to produce a novel olefin derivative of lactide (MML). Olefin CM of MML with hex-1-ene was successful but polymerisation pre- and post-CM was unsuccessful due to monomer instability. CM of another olefin derivative of lactide, 3-methylenated lactide (3-ML) was successful with aliphatic alkenes; hex-1-ene to dodec-1-ene. To overcome competing alcoholysis of the functionalised monomers, which prevented polymerisation, hydrogenation was used to remove the olefin entity followed by successful ring-opening polymerisation (ROP) to produce polymers of low glass-transition temperatures (Tg). Post-polymerisation CM on an olefin containing polymer P(β-heptenolactone) P(β-HL), with methyl acrylate and an epoxide, generated functionalised homopolymers with increased Tg’s. Co-polymerisation of lactide with β-HL generated novel gradient-copolymers. Olefin CM with 15 different cross-partners produced functionalised copolymers with different thermal properties. Based on this route a new methodology was created to introduce two unique functionalities into the polymer backbone by manipulation of the olefin reactivities. Finally, in a collaborative project, uranium and cerium catalysts, Me3SiOU(OArP)3 and Me3SiOCe(OArP)3 - designed out-with the group- were tested and compared as ROP catalysts for lactide. Both catalysts were active in living polymerisations of L-lactide and under immortal conditions the activity and rates of the catalysts were switched, accounted for by a change in the coordination sphere due to ligand displacement. ROP of rac-lactide using the uranium analogue produced heterotactic-biased PLA with a Pr = 0.79.

Dissertação (mestrado)—Universidade de Brasília, Instituto de Letras, Departamento de Linguística, Português e Línguas Clássicas, Programa de Pós-Graduação em Linguística, 2017. / Submitted by Priscilla Sousa (priscillasousa@bce.unb.br) on 2017-10-19T10:53:35Z No. of bitstreams: 1 2017_ÂngelaSousaAraújo.pdf: 7571622 bytes, checksum: 4e563ae4028328d69f3e7292b4a5399a (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2017-11-07T13:10:30Z (GMT) No. of bitstreams: 1 2017_ÂngelaSousaAraújo.pdf: 7571622 bytes, checksum: 4e563ae4028328d69f3e7292b4a5399a (MD5) / Made available in DSpace on 2017-11-07T13:10:30Z (GMT). No. of bitstreams: 1 2017_ÂngelaSousaAraújo.pdf: 7571622 bytes, checksum: 4e563ae4028328d69f3e7292b4a5399a (MD5) Previous issue date: 2017-11-07 / Esta dissertação tem como objetivo analisar o site ‘loecsen.com’ como possível potencial no ensino de Português como Língua Adicional (PLA) por meio da análise de clusters (Baldry & Thibault, 2006) e da ressemiotização (Iedema, 2003). Propor-se-ão reflexões a respeito das características linguísticas existentes no loecsen.com, numa perspectiva discurso-crítica, sobre a importância do ensino mediado no ambiente virtual, considerando que ele dispõe de diversos subsídios que circulam na íntegra como forma de instrumentos para auxiliar os estudantes no desenvolvimento de competências e subcompetências comunicativas e de aprendizagem dos conteúdos de PLA. Os corpora presentes na dissertação foram constituídos de dados extraídos do próprio site loecsen.com. A pesquisa ocupou-se das direções qualitativas de Ferraz (2015), Flick (2009) e Chizzoti (2003). A análise apresentou sua base conforme as seguintes assertivas: 1. Quais recursos semióticos são empregados em websites de ensino de PLA?; 2. O que muda de uma página impressa para uma webpage em termos de língua? e, 3. Qual o potencial significativo de um website no ensino de PLA? A fundamentação teórica teve contribuição da Teoria da Multimodalidade e da Teoria Semiótica (Barton & Lee, 2015), (Kress, 1997), (Iedema, 2003), (Barton, 2015), (Ferraz, 2015), que aliadas deram toda a base teórica que sustentou esta pesquisa em sua íntegra. As concepções de página impressa e webpage apresentadas amadureceram nossas percepções sobre realidade virtual e também sobre a relevância da pesquisa voltada exclusivamente para o ensino mediado pela internet. As semioses exploradas pelo site foram, mais precisamente, as seguintes: oral, escrita e visual, e as utilizadas conforme as normas da Teoria da Multimodalidade, quando usadas uma para complementar a outra gerando por meio dessa interação o sentido almejado. As semioses foram aplicadas ao contexto de aula do site, mas ele não soube aproveitá-las, favorecendo apenas uma aprendizagem periférica e mecânica. A análise do website loecsen.com como mediador de ensino/aprendizagem de português como língua adicional não se revelou um suporte relevante dentro da exploração cada vez mais assídua do ciberespaço pela inexistente interação semiótica e modal que são essenciais na construção de sentido. / This dissertation aims to analyze the site 'loecsen.com' as a potential in the teaching of Portuguese as an Additional Language (PLA) through the analysis of clusters (Baldry & Thibault, 2006) and resemiotization (Iedema, 2003). It will be proposed reflections on the linguistic characteristics of loecsen.com, in a discourse-critical perspective, on the importance of mediated education in the virtual environment, which has several subsidies that circulate in full as a form of instruments for students in the development of communicative skills and subcompetences and learning PLA contents. The corpora of the dissertation were constituted of data extracted from the own site loecsen.com. The research focused on the qualitative directions of Ferraz (2015), Flick (2009) and Chizzoti (2003). The analysis presented its basis according to the following assertions: 1. What semiotic resources are employed in PLA teaching websites?; 2. What changes from a printed page to a webpage in terms of language? and, 3. What is the significant potential of a website in teaching PLA? The theoretical basis was contributed by the Theory of Multimodality and Semiotic Theory (Barton & Lee, 2015), (Kress, 1997), (Iedema, 2003), (Barton, 2015), (Ferraz, 2015), which allies gave the whole theoretical basis that supported this research in its entirety. The conceptions of printed page and webpage presented matured our conceptions about virtual reality and the relevance of the research focused exclusively on the education mediated by the internet. The semioses were explored by the site, more precisely the semioses: oral, written and visual, and used according to the norms of the Multimodality Theory, how much one used to complement the other generating through this interaction the desired meaning. The semioses were applied to the classroom context of the site, but the site did not know how to take advantage of them, favoring only peripheral and mechanical learning. The analysis of the loecsen.com website, as mediator of teaching / learning of Portuguese language, has not proved to be a relevant support within the exploration of cyberspace, more and more assiduous, by the inexistent semiotic and modal interaction essential in the construction of meaning.

Dissertação (mestrado)—Universidade de Brasília, Instituto de Letras, Departamento de Linguística, Português e Línguas Clássicas, Programa de Pós-Graduação em Linguística, 2018. / Submitted by Fabiana Santos (fabianacamargo@bce.unb.br) on 2018-08-23T18:25:07Z No. of bitstreams: 1 2018_LorenaPolianaSilvaLopes.pdf: 2235664 bytes, checksum: d22136a3762dd86d01438eca105ade45 (MD5) / Approved for entry into archive by Raquel Viana (raquelviana@bce.unb.br) on 2018-08-29T17:08:15Z (GMT) No. of bitstreams: 1 2018_LorenaPolianaSilvaLopes.pdf: 2235664 bytes, checksum: d22136a3762dd86d01438eca105ade45 (MD5) / Made available in DSpace on 2018-08-29T17:08:15Z (GMT). No. of bitstreams: 1 2018_LorenaPolianaSilvaLopes.pdf: 2235664 bytes, checksum: d22136a3762dd86d01438eca105ade45 (MD5) Previous issue date: 2018-08-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ). / Esta dissertação tem como tema norteador o ensino de Português como Língua Adicional para a comunidade surda brasileira e a comunidade de fronteira de Puerto Iguazú - Argentina, por meio da Educação Bilíngue. O objetivo principal da pesquisa foi investigar e compreender como agentes como o Estado, por meio de políticas e planejamentos linguísticos, e profissionais da educação, no caso, professores de escolas bilíngues, têm concebido a língua portuguesa em contextos específicos de bilinguismo, bem como averiguar se existe similaridade entre tais concepções e delas com definições teóricas encontradas em estudos linguísticos. Ainda, como recorte do estudo, selecionamos dois projetos de escola bilíngue para análise, o Projeto Escola Pública Integral Bilíngue Libras e Português-Escrito (2011), idealizado pela FENEIS e implantado por uma escola pública em Taguatinga – DF; e o Programa Escolas Bilíngues de Fronteira - PEBF (2008). Para seu desenvolvimento, situamos nosso estudo na abordagem qualitativa e no eixo teórico da Análise de Discurso Crítica – ADC (Fairclough, 2001, 2003), por concebermos a linguagem como parte da prática social, em diálogo com outros conceitos teóricos, sendo os principais os encontrados na Ecolinguística (Couto, 2009) e nos estudos sobre política e planejamento linguístico (Calvet, 2007), status linguísticos (Cunha, 2007; Brandão, 2017), bilinguismo (Martiny e Menoncin, 2013; Mackey, 1968) e diglossia (Ferguson, 1974). Metodologicamente, adotamos as categorias de análise da Análise de Discurso Textualmente Orientada – ADTO, vertente da ADC (2003). O corpus deste estudo é composto por três momentos: o primeiro, denominado levantamento sociolinguístico, foi realizado através de leituras teóricas sobre as comunidades em questão, sob o construto teórico adotado; o segundo, denominado documentos oficiais; e o terceiro, denominado entrevistas, ambos analisados sob a ADTO. Após a transcrição, a geração e a análise dos dados, pudemos obter os seguintes principais resultados: i) os agentes de políticas linguísticas observaram as realidades sociolinguísticas das comunidades-alvo e as concepções teóricas dos status que uma língua pode receber para a elaboração de suas propostas; ii) as professoras entrevistadas demonstraram ter conhecimento e comprometimento com os documentos oficiais, porém não se abstendo de críticas sobre seus conteúdos; e iii) as professoras entrevistadas também possuem concepções particulares sobre o estatuto linguístico da língua portuguesa em suas práticas pedagógicas. Este trabalho pretende, em suma, contribuir para os processos de elaboração de planejamentos linguísticos e de ensino de português como LA em contexto de bilinguismo. / This essay is structured around the teaching of Portuguese as an Additional Language (AL) to the Brazilian deaf community and the bordering community of Puerto Iguazú — Argentina, through Bilingual Education. The main aim of this research is to investigate and understand how agents of the Government, through linguistic politics and plannings, has conceived the Portuguese language in specific bilingual contexts, as well as to ascertain if there are any similarities between such conceptions and their theoretical definitions found in linguistic studies. Also, as a part of this study, we have selected two bilingual school projects for analysis, Projeto Escola Pública Integral Bilíngue Libras e Português-Escrito (2011), a project idealized by FENEIS and executed by a public school in Taguatinga — DF; and Programa Escolas Bilíngues de Fronteira — PEBF (2008). For its development, we have focused our study in the qualitative approach and the theoretical axis of Critical Discourse Analysis — CDA (Fairclough, 2001, 2003), for conceiving language as part of the social practice, in touch with other theoretical concepts, the main ones found in Ecolinguística (Couto, 2009), and the studies on politics and linguistic planning (Calvet, 2007), linguistic status (Cunha, 2007; Brandão, 2017), bilingualism (Martiny and Menoncin, 2013; Mackey, 1968) and diglossia (Ferguson, 1974). Methodologically, we have adopted the analysis categories of the Textually Oriented Discourse Analysis — TODA, a branch of CDA (Fairclough, 2003). The corpus of this study is composed by three parts: the first one, named sociolinguistic data collection, was made through theoretical readings about the aforementioned communities, under the theoretical construct adopted; the second one, titled official documents; and the third one, denominated interviews, both analysed under TODA. After the transcript, the collection and analysis of the data, the following results were obtained: i) the agents in linguistic politics observed the sociolinguistic reality of the target-communities and the theoretical conceptions of the status a language may receive for construction of its proposals; ii) the interviewed teachers demonstrated knowledge and commitment to the official documents, although not keeping criticism of its content to themselves; and iii) the interviewed teachers also have their own conceptions about the linguistic statute of the Portuguese language in their pedagogic practices. This essay intends, in summary, to contribute to the elaboration of linguistic plannings and teaching of Portuguese as an AL in bilingual contexts.

Submitted by Bruna Rodrigues (bruna92rodrigues@yahoo.com.br) on 2016-10-07T11:56:14Z No. of bitstreams: 1 DissDESSce.pdf: 13138783 bytes, checksum: 78ebf6ce0d5a73d4aa71a5155f716c05 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T13:46:38Z (GMT) No. of bitstreams: 1 DissDESSce.pdf: 13138783 bytes, checksum: 78ebf6ce0d5a73d4aa71a5155f716c05 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-10-20T13:46:44Z (GMT) No. of bitstreams: 1 DissDESSce.pdf: 13138783 bytes, checksum: 78ebf6ce0d5a73d4aa71a5155f716c05 (MD5) / Made available in DSpace on 2016-10-20T13:47:21Z (GMT). No. of bitstreams: 1 DissDESSce.pdf: 13138783 bytes, checksum: 78ebf6ce0d5a73d4aa71a5155f716c05 (MD5) Previous issue date: 2013-12-06 / Não recebi financiamento / In recent years, researchers from industry and universities have focused their interests in polymer nanocomposites, especially in multifunctional composites. The composites made from nano expanded graphite ( nGE ) can provide to the polymer matrix an innovative balance of structural, electrical and thermal conductivity, electromagnetic shielding and improved barrier and wear resistance properties. The increasing demand of using biodegradable polymers, such as poly (lactic acid ) (PLA ) and its blends with poly ( butylene succinate) (PBS), in packages of short lifespan with low resistivity requirements, motivated this work. Nanocomposites of nGE with PLA and PLA / PBS blends were evaluated on the effects of conductive nanofiller content and processing methods in their rheological, mechanical, and electrical properties, in order to correlate and possibly control the formation of the percolation network. The nanographite had a major mechanical reinforcement effect in of the composite with PLA / PBS, increasing all tensile properties. Through microstructural analysis, it was was observed the selective localization of graphite particles in PLA, forming a percolated co-continuous phase with PBS phase. This phenomenon was identified as double percolation, result of the preferential nGE gelation in PLA by the processes of coalescence of PBS and possible crystallization of polymers in the blend. The PLA composites remained resistive, since the nGE particles homogeneous dispersion was maintained. The lowest resistivities were found in the samples of the blend processed by compression moulding, more favorable process for the formation of the electrical percolation network through the mechanisms mentioned above. The coalescence of PBS phase proved to be determinant for the electrical percolation. / Nos últimos anos, pesquisadores de indústrias e universidades têm focado seus interesses em nanocompósitos poliméricos, principalmente multifuncionais. Os compósitos e nanocompósitos produzidos a partir de nano grafite expandido (nGE) podem oferecer à matriz polimérica um inovador balanço de propriedades estruturais, condutoras elétricas e térmicas, blindagem eletromagnética e melhores propriedades de barreira e resistência ao desgaste. A crescente demanda pelo uso de polímeros biodegradáveis, como o poli(ácido lático) (PLA) e suas blendas com poli(butileno succinato) (PBS), na fabricação de embalagens de curto tempo de vida e baixa resistividade elétrica motivaram esse trabalho. Nanocompósitos de nGE com PLA e PLA/PBS foram avaliados comparativamente quanto aos efeitos do teor de nanocarga condutiva e métodos de processamento em suas propriedades reológicas, térmicas, mecânicas e elétricas, com o objetivo de correlacionar com a formação da rede de percolação elétrica. As nanolamelas de grafite apresentaram um grande efeito de reforço mecânico nos compósitos com a blenda PLA/PBS, o que aumentou todas as propriedades em tração. Através de análise microestrutural, foi constatada a localização seletiva das nanopartículas de grafite no PLA formando uma fase percolada e co-contínua com a fase de PBS. Esse fenômeno foi identificado como percolação dupla, resultado da aglomeração preferencial do nGE no PLA por processos de coalescência do PBS e possível cristalização dos polímeros na blenda. Os compósitos apenas com PLA se mantiveram resistivos, já que as partículas de nGE se mantiveram mais homogeneamente dispersas. As menores resistividades foram encontradas nas amostras da blenda moldada por compressão, processo mais favorável para a formação da rede de percolação elétrica através dos mecanismos citados acima. A coalescência da fase de PBS se mostrou determinante para a percolação elétrica.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2015-11-27T15:18:54Z No. of bitstreams: 1 BrismarkGoesDaRocha_TESE.pdf: 14655007 bytes, checksum: f132218e797f47b22250ea1afea1399e (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2015-11-30T21:25:07Z (GMT) No. of bitstreams: 1 BrismarkGoesDaRocha_TESE.pdf: 14655007 bytes, checksum: f132218e797f47b22250ea1afea1399e (MD5) / Made available in DSpace on 2015-11-30T21:25:07Z (GMT). No. of bitstreams: 1 BrismarkGoesDaRocha_TESE.pdf: 14655007 bytes, checksum: f132218e797f47b22250ea1afea1399e (MD5) Previous issue date: 2014-07-30 / O presente trabalho tem como objetivos extrair a fibra da folha do abacaxizeiro tipo P?rola para obter bast?es (?whiskers) de celulose destas fibras tratadas quimicamente, para utiliza??o como refor?o na fabrica??o de filmes de Biocomp?sito com Poli ?lcool Vin?lico (PVA) e Poli (?cido l?tico) (PLA) como matrizes. As amostras foram caracterizadas utilizando an?lises como TGA, FTIR e DSC. Tamb?m foram realizados ensaios das folhas para a identifica??o de macro e micro nutrientes. As amostras dos filmes de biocomp?sitos foram usadas para ensaios mec?nicos de tra??o nos filmes e o teste de biodegrada??o aer?bica, bem como nos filmes de 100% de PVA e PLA. A extra??o da fibra foi efetuada numa desfibradeira autom?tica, e em seguida as fibras extra?das foram lavadas v?rias vezes para remover as impurezas e foram tratadas com NaOH (hidr?xido de s?dio) e NaClO (hipoclorito de s?dio), para remover as impurezas inerentes ?s fibras e a cor natural, respectivamente. Em seguida, as fibras tratadas foram submetidas a um processo de hidr?lise com ?cido sulf?rico a 13,5%, para obten??o de bast?es de celulose. Foram produzidos filmes biocomp?sitos de PVA e PLA com bast?es de celulose nas concentra??es de 0%, 1%, 3%, 6%, 9% e 12%. ?gua destilada a 80?C ? 5 na dilui??o de PVA e diclorometano para a dilui??o do PLA na temperatura ambiente. Na prepara??o dos filmes foi utilizado o m?todo de ?casting?. Posteriormente foram realizados os testes de absor??o de ?gua pelos filmes produzidos. Para o ensaio mec?nico de tra??o dos filmes foi utilizada a norma ASTM D638-10 com velocidade de 50 mm/min. O teste estat?stico Qui-quadrado foi empregado para a verifica??o da exist?ncia de diferen?as significativas em n?vel de 0,05: comprimentos das folhas do abacaxizeiro e dos bast?es, procedimentos utilizados para filtra??o em filtro utilizando seringa de 0,2 ?m e filtragem atrav?s de centrifuga??o. Foi realizado estudo de hidrofilidade dos filmes com base no ?ngulo de contato. Tamb?m foi aplicado o teste Estat?stico T-Student com n?vel de signific?ncia (0,05) para comparar as espessuras dos filmes de PVA e PLA e das propriedades mec?nicas (tra??o). Na avalia??o da biodegradabilidade dos biocomp?sitos, bem como os filmes de 100% das matrizes de PVA e PLA, foi utilizado o teste de Sturm norma D5209. Os resultados indicam a presen?a de bast?es de celulose com comprimentos variandos de 7,33 nm a 186,17 nm. As espessuras em m?dia dos filmes de PVA e PLA eram de 0,153 ?m e 0,210 ?m, respectivamente. Foi observada uma forte correla??o linear diretamente proporcional entre a tra??o dos filmes de PVA e a concentra??o de bast?es de celulose nos filmes (0,7336), da espessura do filme de 0,1404. Juntos, a porcentagem de bast?es de celulose e a espessura dos filmes, correlacionaram 0,8740. No caso dos filmes de PLA, a correla??o entre o teor dos bast?es de celulose e a tra??o foi fraca, inversamente proporcional (-0,0057) e a espessura em -0,2602, totalizando -0,2659, isto ?, os bast?es de celulose n?o aderiram totalmente ao PLA. Na compara??o dos resultados da tra??o das duas matrizes polim?ricas, os bast?es de celulose contribu?ram na melhoria das propriedades mec?nicas no caso de PVA, mas h? uma diferen?a com rela??o a PLA. Nos testes de biodegradabilidade, foi observado a degrada??o total do filme de PVA ap?s 27 dias, enquanto o filme de PLA degradou em 20 dias, o que comprova que os filmes produzidos s?o biodegrad?veis. / This work has the main objective to obtain nano and microcrystals of cellulose, extracted from the pineapple leaf fibres (PALF), as reinforcement for the manufacture of biocomposite films with polymeric matrices of Poly(vinyl alcohol) (PVA) and Poly(lactic acid) (PLA). The polymer matrices and the nano and microcrystals of cellulose were characterised by means of TGA, FTIR and DSC. The analysis was performed on the pineapple leaves to identify the macro and micronutrients. The fibers of the leaves of the pineapple were extracted in a desfibradeira mechanical. The PALF extracted were washed to remove washable impurities and subsequently treated with sodium hydroxide (NaOH) and sodium hypochlorite (NaClO) in the removal of impurities, such as fat, grease, pectates, pectin and lignin. The processed PALF fibers were hydrolysed in sulfuric acid (H2SO4) at a concentration of 13.5 %, to obtain nano and microcrystals of cellulose. In the manufacture of biocomposite films, concentrations of cellulose, 0 %, 1 %, 3 %, 6 %, 9% and 12% were used as reinforcement to the matrices of PVA and PLA. The PVA was dissolved in distilled water at 80 ? 5 oC and the PLA was dissolved in dichloromethane at room temperature. The manufacture of biocomp?sitos in the form of films was carried out by "casting". Tests were carried out to study the water absorption by the films and mechanical test of resistance to traction according to ASTM D638-10 with a velocity of 50 mm/min.. Chi-square statistical test was used to check for the existence of significant differences in the level of 0.05: the lengths of the PALF, lengths of the nano and microcrystals of cellulose and the procedures used for the filtration using filter syringe of 0.2 ?m or filtration and centrifugation. The hydrophilicity of biocomp?sitos was analysed by measuring the contact angle and the thickness of biocomp?sitos were compared as well as the results of tests of traction. Statistical T test - Student was also applied with the significance level (0.05). In biodegradation, Sturm test of standard D5209 was used. Nano and microcrystals of cellulose with lengths ranging from 7.33 nm to 186.17 nm were found. The PVA films showed average thicknesses of 0.153 ?m and PLA 0.210 ?m. There is a strong linear correlation directly proportional between the traction of the films of PVA and the concentration of cellulose in the films (composite) (0,7336), while the thickness of the film was correlated in 0.1404. Nano and microcrystals of cellulose and thickness together, correlated to 0.8740. While the correlation between the cellulose content and tensile strength was weak and inversely proportional (- 0,0057) and thickness in -0.2602, totaling -0,2659 in PLA films. This can be attributed to the nano and microcrystals of cellulose not fully adsorbed to the PLA matrix. In the comparison of the results of the traction of the two polymer matrices, the nano and microcrystals have helped in reducing the traction of the films (composite) of PLA. There was still the degradation of the film of PVA, within a period of 20 days, which was not seen in the PLA film, on the other hand, the observations made in the literature, the average time to start the degradation is above 60 days. What can be said that the films are biodegradable composites, with hydrophilicity and the nano and microcrystals of cellulose, contribute positively in the improvement of the results of polymer matrices used.

The principal aim of this diploma thesis was the mapping of amphibian species inhabiting the Protected Landscape Area Blaník. The field research was carried out during the years 2005 to 2006. The occurrence of following 8 species and 1 synklepton was confirmed: Smooth Newt (Triturus vulgaris), Warty Newt (Triturus cristatus), Alpine Newt (Triturus alpestris), Fired Bellied Toad (Bombina bombina), Common Spadefood (Pelobates fuscus), Common Toad (Bufo bufo), European Tree Frog (Hyla arborea), Grass Frog (Rana temporaria) and Water Frogs (Rana synklepton esculenta). The determination was performed on the basis of morphologic characters and voice expressions. During the field research suitable reproductive habitats of particular species were studied with respect to numbers of specimens found there. Based on presented results, habitats valuable for protection mere marked. The records of particular species were written into maps of the species occurance.

Submitted by Rosa Assis (rosa_assis@yahoo.com.br) on 2016-09-22T13:50:32Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Rafael Soares Silva.pdf: 2923341 bytes, checksum: a831738a4d83ca6103e1489945754a7b (MD5) / Made available in DSpace on 2016-09-22T13:50:32Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Rafael Soares Silva.pdf: 2923341 bytes, checksum: a831738a4d83ca6103e1489945754a7b (MD5) Previous issue date: 2016-05-20 / This study aimed to evaluate the effects of additives (primary and secondary antioxidants) in thermal stabilization process of poly (lactic acid) / poly (butylene adipate-co-terephthalate) - PLA / PBAT using a torque rheometer as a preliminary tool evaluation of the stabilization process. The additives Irganox 1010, Irganox 1076, Irganox B900, Irgafos 168, and a flavonoid were used in two concentrations, 0.3 and 0.5% w/w. The assessment of the effects of stabilizing additives was carried out by monitoring the torque during mixing molar mass measurements, infrared analysis, turbidity and Scanning Electron Microscopy of the samples after processing. It carried out the monitoring of the pure blend torque values and addition of stabilizing additives during processing up to 5 minutes in an internal mixer of the type "mixer" under rotation of 60 rpm and a temperature of 180 °C. Within a series of primary and secondary antioxidants, it was found that some of these additives failed torque values greater than or similar to the pure blend at certain concentrations (Irganox 1076, Irganox B900 and Irgafos 168). molar mass measurements showed that pure processed blend undergoes a large number of chain scission and most additives stabilizing action achieved unless the flavonoid. One important information obtained through analyzes of torque rheometry and molar mass that is higher drying time strongly prevents hydrolysis reactions. Comparing the infrared spectra of pure and pure blend blend processed, there is not the appearance of no new peak occurs due to the degradative process. By UV-Vis analysis of the polymer solutions we verified the presence of crosslinked polymer microstructures due to thermo-oxidative reactions. Images obtained by scanning Elletrônica Microscopy (SEM), one can observe the presence of two distinct phases for the pure blend processed, and the use of additives in both compositions show a much smaller difference of phases to blend pure. These results indicate the possibility of using commercial additives used for non-biodegradable polymers in systems using biodegradable polymers. / Este trabalho teve como objetivo avaliar a ação de aditivos (antioxidantes primários e secundários) no processo de estabilização térmica da blenda poli(ácido láctico)/poli(butileno adipato-co-tereftalato) - PLA/PBAT usando um reômetro de torque como ferramenta prévia de avaliação do processo de estabilização. Os aditivos Irganox 1010, Irganox 1076, Irganox B900, Irgafos 168 e o Flavonóide foram usados em duas concentrações, 0,3 e 0,5% em massa. A avaliação dos efeitos dos aditivos estabilizantes foi realizada por meio de monitoramento do torque durante mistura, medidas de massa molar, análises de infravermelho, turbidez e microscopia eletrônica de varredura das amostras após processamento. Realizou-se o monitoramento dos valores de torque da blenda pura e com adição de aditivos estabilizantes durante processamento por até 5 minutos em um misturador interno do tipo “Mixer” sob rotação de 60 rpm e temperatura de 180 oC. Dentro de uma série de antioxidantes primários e secundários, verificou-se o uso de alguns desses aditivos conseguiram valores de torque superior ou semelhante ao da blenda pura em determinadas concentrações (Irganox 1076, Irganox B900 e Irgafos 168). Medidas de massa molar mostraram que a blenda pura processada sofre um grande número de cisão de cadeias e que a maioria dos aditivos conseguiram ação estabilizante menos o flavonóide. Uma informação importante obtida por meio das análises de reometria de torque e massa molar é que um tempo maior de secagem evita fortemente as reações de hidrólise. Comparando-se os espectros de infravermelho da blenda pura e da blenda pura processada, nota-se que não aparecem nenhum novos picos relacionados ao processo degradativo. Através da análise de UV-Vis das soluções poliméricas verificou-se a presença de microestruturas poliméricas reticuladas em virtude das reações termo-oxidativas. Imagens obtidas por Microscopia Elletrônica de varredura (MEV), evidenciam a presença de duas fases distintas para a blenda pura processada, e o uso dos aditivos nas duas composições mostram uma diferenciação das fases muito menor que para blenda pura. Esses resultados indicam que existe a possibilidade do uso de aditivos comerciais usados para polímeros não-biodegradáveis em sistemas com polímeros biodegradáveis.

Submitted by Rosa Assis (rosa_assis@yahoo.com.br) on 2017-11-13T17:34:41Z No. of bitstreams: 2 Natália Góes dos Santos Barom.pdf: 3214358 bytes, checksum: 06d4cb5193343cfbe74d31c02ad2e0f1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2017-12-07T11:53:52Z (GMT) No. of bitstreams: 2 Natália Góes dos Santos Barom.pdf: 3214358 bytes, checksum: 06d4cb5193343cfbe74d31c02ad2e0f1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-12-07T11:53:52Z (GMT). No. of bitstreams: 2 Natália Góes dos Santos Barom.pdf: 3214358 bytes, checksum: 06d4cb5193343cfbe74d31c02ad2e0f1 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2011-08-31 / Não consta abstract no trabalho / Não consta resumo no trabalho