Bottlebrush polymers are interesting topologies that have become increasingly relevant in various applications including rheology modifiers, super-soft elastomers, photonic crystals, anti-fouling coatings, the in vivo delivery of therapeutic agents, and as promising substrates in lithographic printing. These macromolecules are comprised of numerous polymeric side-chains densely grafted to a polymer backbone. The densely grafted nature of bottlebrush polymers results in steric repulsion between neighboring polymer chains, forcing these macromolecules to adopt a chain-extended conformation. Although these remarkable macromolecules have a many different applications, the transformative potential of the bottlebrush polymer topology has not been realized because the synthesis of high molecular weight bottlebrush polymers is challenging. This dissertation focusses on improving the synthesis of these large macromolecules using the grafting-through strategy in the first section and the transfer-to strategy in the second section. For the first time the effect of anchor group chemistry—the configuration of atoms linking the polymer to a polymerizable norbornene—was studied on the kinetics of ring-opening metathesis polymerization (ROMP) of macromonomers (MMs) initiated by Grubbs 3rd generation catalyst. A variance in the rate of propagation of >4-fold between similar MMs with different anchor groups was observed. This phenomenon was conserved across all MMs tested, regardless of solvent, molecular weight (MW), or repeat unit identity. Experimental and computational studies indicated that the rate differences likely resulted from a combination of varying steric demands and electronic structure among the different anchor groups. This new insight will allow others to achieve high MM conversion and prepare pure, high MW bottlebrush polymers by ROMP grafting-through. The second section of this dissertation deals with a little studied bottlebrush synthesis technique called the transfer-to method. This method is a hybrid of the grafting-from and grafting-to approaches in which the growing polymer side chains detach from the backbone, propagate freely in solution, and then reattach to the backbone in a chain transfer step. Several parameters were investigated to determine optimal conditions for this process. This study provides for the first time a guide to use the transfer-to method to produce high purity bottlebrush polymers with controllable backbone and side chain length. / Ph. D.

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Yes / This paper seeks to contribute to the debate around sustainability by proposing the need for an ecocentric stance to sustainability that reflexively embeds humans in—rather than detached from—nature. We argue that this requires a different way of thinking about our relationship with our world, necessitating a (re)engagement with the sociomaterial world in which we live. We develop the notion of ecocentrism by drawing on insights from sociomateriality studies, and show how radical-reflexivity enables us to appreciate our embeddedness and responsibility for sustainability by bringing attention to the interrelationship between values, actions and our social and material world. We examine the implications of an ecocentric radically reflexive approach to sustainability for management education.

The aim of this work was to successfully prepare polymers of N-(2-hydroxypropyl)methacrylamide, (PHPMA) using controlled/"living" free-radical polymerisation technique. For this purpose, atom transfer radical polymerisation (ATRP) and reversible addition-fragmentation (chain) transfer (RAFT) polymerisation were used in preparation of a number of base polymers with the intention of quantitatively converting them into PHPMA. Both methods were applied under varying polymerisation conditions, and the kinetics of the systems investigated. Various rate constants were measured, while computer modelling of the experimental data allowed estimation of other kinetic parameters of interest. Investigations into solvent and ligand effects on the kinetics of ATRP of the activated ester methacryloyloxy succinimide (MAOS) and one of the archetypal methacrylate monomers, methyl methacrylate (MMA) were carried out. The method of RAFT was also employed in polymerisation of MAOS and a number of other monomers in the hope of finding the best synthetic precursor of PHPMA. Polymers of methacryloyl chloride (MAC) and p-nitrophenyl methacrylate (NPMA) were prepared, as well as the polymers of HPMA itself and N-isopropyl methacrylamide. Polymerisation of MMA by RAFT was also attempted in view of adding to current knowledge on the monomer's behaviour and the kinetic characteristics of its RAFT polymerisation. Preparation of PHPMA from PMAOS, PMAC and PNPMA was attempted. Successful preparation of PHPMA from the polymer of the acid chloride was achieved under mild reaction conditions, while displacement of N-hydroxysuccinimide groups of PMAOS resulted in unexpected modification of the polymer under the conditions used. Conversion of PNPMA into PHPMA was not achieved. At this stage these results suggest inadequacy of both PMAOS and PNPMA as reactive polymeric precursors.

Aerosols of nitrate solutions were irradiated in the presence of radical scavengers in an attempt to measure the yield of hydroxyl radical in both the aqueous phase and the gas phase. Carbon monoxide, benzoic acid, benzene and cyclohexane were used as scavengers to trap hydroxyl radical. The products from the reaction of these scavengers with hydroxyl radical were analysed with High Performance Liquid Chromatography and mass spectrometry. The radiant flux in the chamber was measured via ferrioxalate actinometry, both with bulk liquid and aerosol droplets. Many quantitative results were obtained but several anomalies were found. This suggests that Mie theory is not capable of predicting rates of photochemical reactions within droplets.

This thesis illuminates meaning(s) of religion in a Swedish radical nationalist context. The empirical study is based on a critical text analysis of author Jonas De Geer, key ideology producer of Swedish radical nationalism. The research questions concern how the publications of Jonas De Geer, during the period 1996-2016, address issues related to religion and Christian imagery. The primary aim of the thesis – to study how the concept of religion is understood, negotiated and used in a Swedish radical nationalist context – is enunciated through an examination of how identity and antagonists are construed through the notions of religion in the material, and how these concepts change over time. An applied text analysis, informed by critical discourse analysis and corpus linguistics, constitutes the methodological framework of the study. The empirical analysis suggests that Christianity and national identity are construed as intertwined and natural, while Judaism is portrayed as the primary antagonist. Additionally, Islam and modernist ideals are depicted as weapons used by Jewish influence to dominate the West. Drawing on these empirical implications, the study concludes that religion functions as a racist configuration in De Geer's symbolic universe.

Os efeitos de ribonucleosídeos de guanina substituídos na posição C-8 na proliferação de linfócitos B estão bem documentados na literatura. Esses compostos são análogos de adutos formados pela adição de radicais livres a ribonucleosídeos e a RNA. Neste trabalho, verificamos as propriedades proliferativas de dois desses adutos, 8-metilguanosina (8-MeGuo) e 8-oxo-7 ,8-di-hidroguanosina (8-OxoGuo) e comparamos com 8-bromoguanosina (8-BrGuo), o composto mais estudado como indutor da proliferação de linfócitos B. 8-MeGuo e 8-OxoGuo foram sintetisados em rendimentos de 28 e 55%, respectivamente, e foram caracterizados por UV, NMR e CG-massa. Seus efeitos sobre a incorporação de timidina radioativa ([3H] TdR) no DNA de células de baço, fibroblasto 3T3(A31) e melanoma B16F10 foram examinados. Os dois adutos foram mitogênicos para células de baço mas foram seletivos quanto as células imortalizadas. 8-MeGuo atuou sobre células 3T3(A31) e 8-OxoGuo sobre as células de melanoma B16F10. O análogo não fisiológico 8-BrGuo foi efetivo em todas as células testadas. Experimentos de contagem de células, citotoxicidade e citometria de fluxo, indicaram que a síntese de DNA induzida pelas guanosinas substituídas na posição C-8 refletia crescimento celular. Foi proposto que os compostos agem de dentro da célula uma vez que seus efeitos são bloqueados em presença de um inibidor de transporte de nucleosídeo, mas não foram inibidos por um antagonista de receptor purinérgico. Os resultados obtidos, junto com os descritos na literatura, sugerem que no caso dos fibroblastos 3T3(A31) e células de baço de camundongo os efeitos proliferativos dos compostos não são dependentes do metabolismo desses compostos via salvação das purinas. No caso das células de melanoma, entretanto, os compostos parecem fazer parte do \"pool\" de nucleosídeos. A demonstração de que adutos produzidos por ataques radicalares em ribonucleosídeos e RNA são capazes de induzir proliferação celular, abre novas perspectivas para a compreensão do papel de radicais livres em processos carcinogênicos. / The ability of CS-substituted guanine ribonucleosides to induce B cell proliferation has been well documented in the literature. These compounds are analogues of adducts formed from free radical attack on ribonucleosides and RNA. Here we examined the proliferative properties of two of these radical adducts, 8-methylguanosine (8-MeGuo) and 8-oxo-7 ,8-dihydroguanosine (8-OxoGuo) and compared them with those of the well studied B cell mitogen, 8-bromoguanosine (8-BrGuo). 8-MeGuo and 8-OxoGuo were synthesized in yields of 28 and 55 %, respectively, and were characterized by UV, NMR and CG-MS. Their effects upon [3H] thymidine uptake by Swiss mice splenocytes, mouse embryo 3T3 (A31) fibroblasts and mouse B16F10 melanocytes were examined. Both guanosine radical adducts were shown to increase [3H] thymidine uptake by mice splenocytes but displayed selectivity in regard to continuous cell lines. 8-MeGuo acted upon 3T3(A31) fibroblasts whereas 8-OxoGuo acted upon B16F10 melanocytes. The non physiological analogue 8-BrGuo acted upon all tested cells. Parallel experiments of cell counting, cytotoxicity, and cell sorting indicated that DNA synthesis induced by the C8-substituted guanosines reflected cell growth. It is proposed that the compounds act intracellularly because their proliferative effects were blocked in the presence of a nucleoside transport inhibitor but were not inhibited by an antagonist of the A2 purine receptor. The obtained results, taken together with data from the literature suggest that in the case of 3T3 (A31) fibroblasts and mice splenocytes the proliferative effects of the compounds are not dependent on metabolism through purine salvage pathways. In the case of melanocytes, however, the compounds are likely to become part of the purine nucleoside pool. The demonstration that adducts produced by free radical attack on ribonucleosides and RNA are able to induce cell proliferation opens new perspectives for the understanding of free radical mediated carcinogenesis.

O Brasil possui uma imensa diversidade biológica, na qual muitos compostos bioativos podem ser encontrados e utilizados em beneficio à sociedade. No entanto, processos de degradação do ambiente e introdução de espécies exóticas têm contribuído ao conhecimento e uso limitadosde muitas plantas nativas, sendopequena a quantidade de estudos sobre sua composição química e potencial biológico. A prevenção de doenças crônicas constantemente vem sendo associada à atividade antioxidante de metabólitos secundários dos vegetais, principalmente os fenólicos. Assim, o objetivo deste trabalho foi avaliar a atividade antioxidante e composição fenólica de cinco espécies frutíferas nativas do Brasil (G. brasiliensis, E. leitonii, E. involucrata, E. brasiliensis e E. myrcianthes). Os métodos capacidade de redução do Folin-Ciocalteau, autoxidação do sistema ?-caroteno/ácido linoleico, capacidade de absorção de radicais oxigênio (ORAC), sequestro dos radicais livres DPPH e ânion superóxido foram aplicados na determinação da atividade antioxidante dos extratos etanólicos de folha, casca, semente e polpa das espécies selecionadas. As amostras demonstraram significativa atividade antioxidante e, em alguns casos, superior as frutas comumente consumidas pela população brasileira. Em geral, folhas apresentaram as maiores atividades, mas o destaque foi a semente de E. leitonii que exibiu os melhores resultados em quatro dos cinco métodos utilizados: 120,67 mg AG.g-1 na redução do reagente Folin; 7,08 Gmol Trolox.g-1 no ?-caroteno; EC50 de 0,26 mg.mL-1 e 0,07 mg.mL-1 no sequestro do ânion superóxido e DPPH, respectivamente; 514,75 Gmol Trolox.g-1 no ORAC para o qual a folha de E. involucrata obteve o maior valor (1393,3 Gmol Trolox.g-1). Os extratos das espécies nativas também demonstram efeito antioxidante contra radicais de relevância biológica, como peroxila e superóxido. Por meio de CG-EM e CLAE acoplado a arranjo de fotodiodos, os principais compostos fenólicos encontrados nos extratos vegetais foram catequina, epicatequina e ácido gálico. Este trabalho demonstrou o grande potencial antioxidante das frutíferas nativas brasileiras, evidenciando assim possível efeito positivo em sistemas biológicos. / Brazil has a great biodiversity, in which many bioactive compounds can be found and used to benefit the society. However, environmental degradation processes and introduction of exotic species have contributed to limited use and knowledge of many native plants, reflecting in few studies about chemical composition and biological potential. The prevention of chronic diseases has been constantly associated with the antioxidant activity of plants secondary metabolites, mainly the phenolics. The objective of this study was to evaluate the antioxidant activity and the phenolic composition of five Brazilian native fruitful species (G. brasiliensis, E. leitonii, E. involucrata, E. brasiliensis e E. myrcianthes). The methods of Folin-Ciocalteau reducing capacity, co-oxidation of ?-carotene/linoleic acid system, oxygen radical absorbance capacity (ORAC), DPPH and superoxide free radical scavenging were used to determine the antioxidant activity of ethanolic extracts of leaf, peel, seed and pulp of the selected species. The samples showed significant antioxidant activity and, in some cases, it was superior to fruits commonly consumed by Brazilian population. In general, leaves presented the highest activities, but the seed of E. Leitonii stood out exhibiting the best results in four of the five methods: 120.67 mg GA.g-1 in the Folin reducing; 7.08 Gmol Trolox.g-1 in the ?-carotene; EC50 of 0.26 mg.mL-1 and 0.07 mg.mL-1 in the superoxide and DPPH scavenging, respectively; 514.75 Gmol Trolox.g-1 in the ORAC, for which the E. Involucrata leaf had the highest value (1393.3 GmolTrolox.g-1). The extracts of native species also demonstrate antioxidant effect against radicals of biological relevance, such as peroxyl and superoxide. By GC-MS and HPLC coupled to a photodiode array, the major phenolic compounds found in the plant extracts were catechin, epicatechin and gallic acid. In this study, Brazilian native fruitful presented high antioxidant potential, showing a possible positive effect on biological systems.

Este trabalho busca compreender as amarras e as potencialidades em torno do uso das mídias digitais por ativistas autônomos anticapitalistas. O objetivo é partir da discussão sobre a potência democratizante que a Internet ativa e chegar à análise de coletivos autônomos que produzem e divulgam no espaço digital um discurso anticapitalista. Embora as novas mídias façam parte da indústria na qual a informação é mercadoria e meio de reprodução da lógica de produção vigente, a existência de grupos que usufruem das mídias digitais para criticar o atual modelo político, econômico e social contribui para o crescimento descentralizado da construção e difusão do pensamento antissistêmico. Portanto, interessa a esta pesquisa refletir sobre as origens desse ativismo e seu potencial de transformação social. A narração de episódios recentes da trajetória do movimento autônomo - o levante zapatista, a Ação Global dos Povos e as ocupações de 2011- vai ajudar na compreensão de elementos encontrados nos protestos de junho de 2013 e na formação de uma rede de coletivos em espaços físicos e virtuais. A coleta de dados de redes sociais e entrevistas com militantes basearão a descrição das ações comunicativas empreendidas por esses ativistas. / This paper seeks to understand the limits and potentialities surrounding the use of digital media by autonome anticapitalist activists. The purpose is to depart from the discussion about the democratizing potency that Internet activates and reach the analysis of autonome movements that produce and publish in the digital environment an anticapitalist speech. Although new media takes part of industry where information is merchandise and way of reproducing the logic of the current production, the existence of groups that take advantage of digital media to criticize the current political, economic and social model contributes to the decentralized growth of construction and dissemination of antisystemic thought. Therefore, this research is interested in reflect on the origins of this activism and its potential for social transformation. The narration of recent episodes of the trajectory of the autonomous movement - the Zapatista insurrection, the People\'s Global Action and occupations in 2011 - will help in the understanding of elements found in the protests of June 2013 and the formation of a network of collectives in physical and virtual spaces. The collection of data from social networks and interviews with militants will base the description of communicative actions undertaken by these activists.

A alimentação deve fornecer nutrientes essenciais em equilíbrio. A carne é uma perfeita fonte de proteína e fornece ferro, zinco e várias vitaminas, no entanto a carne vermelha e produtos à base de carne também mantêm o risco da indução de estresse oxidativo, por meio da formação catalisada de radicais livres por ferro durante a digestão. Uma dieta equilibrada deve ser inspirada pela natureza. Com a evolução, a natureza teve que lidar com o estresse oxidativo em um ambiente com um aumento da concentração de oxigênio e exposição à luz UV variando sazonalmente. Carotenoides têm sido considerados protetores do sistema responsável pela fotossíntese, suprimindo o oxigênio ativado e captando os radicais livres, evitando que estruturas sensíveis sejam destruídas. Polifenóis, onipresentes no reino vegetal, tornaram-se essenciais para a proteção contra luz UV, controle de metais livres e danos mecânicos, quando tocotrienóis e tocoferóis associam-se a membranas promovendo sua proteção. Um desafio hoje é entender o mecanismo por trás das várias classes de protetores contra o estresse oxidativo e, especialmente, sua interação sinérgica e usar esse entendimento para melhorar a nossa dieta. As diferentes classes de compostos bioativos, incluindo captores de radicais livres, supressores do estado excitado, quelantes de metais e reguladores de genes mantêm uma diversidade estrutural e funcional apenas parcialmente compreendida e explorada. Nesse momento é importante um olhar mais atento para essa biodiversidade em relação à composição dos nossos alimentos com foco em um consumo seguro de carne, como parte de uma dieta equilibrada. O Brasil em sua rica e vasta flora detém alguns dos maiores recursos botânicos não explorados do mundo. Hoje o desafio científico é fazer a ingestão de carne vermelha mais segura, e ainda uma fonte confiável de ferro e outros minerais. Olhando para este desafio, o presente trabalho visou selecionar frutas pouco exploradas do Cerrado brasileiro como uma fonte de antioxidantes na dieta. Frutas do Cerrado foram primeiramente selecionadas com base nas características sensoriais, os frutos selecionados foram avaliados pelas concentrações totais de fenóis, flavonoides, taninos, glicídios, antocianinas e ácido ascórbico. Suas propriedades antioxidantes foram investigadas com base na capacidade de captar radicais 1-hidroxietila e reduzir o pigmento hipervalente de carne (ferrilmioglobina) no sistema modelo. / Human food must supply essential nutrients in balance. Meat is a perfect protein source and supplies iron and zinc and many vitamins, although red meat and meat products also hold the risk of inducing oxidative stress through iron-catalyzed formation of free radicals during digestion. A balanced diet should be inspired by nature. Through evolution, nature has had to deal with oxidative stress in an atmosphere with an increasing oxygen content and UV light exposure with seasonal variations. Carotenoids merged as protectors of the photosynthetic apparatus to quench activated oxygen and to scavenge free radicals otherwise destroying sensitive structures. Polyphenols, ubiquitous in the plant kingdom, became essential for surface protection against UV light, control of free metals and mechanical damage, while tocotrienols and tocopherols became associated with membranes promoting their protection. A challenge today is to understand the mechanism behind the various classes of protectors against oxidative stress and especially their synergic interaction and to use this understanding to improve our diet. The different classes of bioactive compounds including free radical scavengers, excited-state quenchers, metal chelators and gene regulators hold a structural and functional diversity only partly understood and explored. It has become time for a closer look into this biodiversity in relation to the composition of our food with focus on a safe meat intake as part of a balanced diet. Brazil holds some of the world\'s largest unexploited botanical resources in the rich and to a large degree unexplored flora. Today scientific challenge is to make red meat intake safer but still a trustworthy source of iron and other minerals. Looking into this challenge, the present work aim to select underexplored fruits from the brazilian Cerrado as a source of dietary antioxidants. Fruits from the Cerrado were first selected based on the sensorial characteristic, the selected fruits were evaluated with their total content of polyphenols, flavonoids, tannins, glycides, anthocyanins, and ascorbic acid. They were further investigated for their antioxidant properties based on the ability to scavenge 1-hydroxyethyl radical and to reduce the biological relevant hypervalent meat pigment (ferrylmyoglobin) in model system.