Thesis (Ph. D.)--University of Chicago, Dept. of Art History, June 2003. / Includes bibliographical references. Also available on the Internet.

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O estudo busca esclarecer pontos essenciais sobre o emprego da termocromia em têxteis por meio de sua aplicação em estampas em camisetas, respondendo questões sobre o poder expressivo destas e do uso da termocromia como recurso de qualificação em projetos de Design de Superfície. A pesquisa traz dados históricos da camiseta como objeto de design e moda. Nesse contexto verificou-se a relevância dos esclarecimentos técnicos sobre o funcionamento da tinta termocrômica, assim como apresenta-se no estudo uma gama de produtos que se utilizaram da aplicação desta técnica, além de estudos acadêmicos considerados inovadores nessa área de conhecimento. O objetivo principal do estudo é explorar novos conhecimentos sobre os sistemas e técnicas em relação à aplicabilidade da termocromia em estampas de camisetas, bem como mostrar as capacidades subjetivas de comunicação/expressão e de interatividade em produtos com essa tecnologia, que podem servir como auxílio para os designers em projetos inovadores. Neste sentido, foram propostos estudos experimentais de aplicação de estampas com tinta termocrômica em camisetas, que deram o sentido fundamental a esta dissertação, acrescentando conhecimento e abrindo espaço para novas pesquisas no âmbito interdisciplinar. Neste estudo de caso exploratório, foi possível concluir, que os métodos mostrados aqui são fatores importantes de inovação para o setor têxtil e de moda e que os testes produzidos provaram a necessidade de rigor técnico contido nas especificações técnicas do fornecedor. / This study aims to clarify some fundamental questions related to textile thermochromism in the application of t-shirt printing, namely the expressive power of prints and the use of thermochromism as a resource in surface design. The investigation brings historical data regarding the t-shirt as an object of design and fashion. In this context, the importance of technical clarification related to the performance of thermochromic ink is verified and a range of products utilized in this technique are presented. A number of innovative academic studies in this area are also presented. The main objectives of this study are to investigate new knowledge about the applicability of systems and techniques utilized in thermochromic t-shirt graphics and to demonstrate the subjective capacity of expression and interaction of products that utilize this technology, which can serve as an aid to designers in innovative projects. From this perspective, experimental tests in the application of thermochromic t-shirt printing were proposed, providing significance to this thesis, enhancing the knowledge in this field and promoting further interdisciplinary research. In this exploratory case study it was possible to conclude that the methods shown here represent important innovations in the textile and fashion sectors and that the tests demonstrated the necessity of technical rigor regarding manufacturers’ technical specifications.

O estudo busca esclarecer pontos essenciais sobre o emprego da termocromia em têxteis por meio de sua aplicação em estampas em camisetas, respondendo questões sobre o poder expressivo destas e do uso da termocromia como recurso de qualificação em projetos de Design de Superfície. A pesquisa traz dados históricos da camiseta como objeto de design e moda. Nesse contexto verificou-se a relevância dos esclarecimentos técnicos sobre o funcionamento da tinta termocrômica, assim como apresenta-se no estudo uma gama de produtos que se utilizaram da aplicação desta técnica, além de estudos acadêmicos considerados inovadores nessa área de conhecimento. O objetivo principal do estudo é explorar novos conhecimentos sobre os sistemas e técnicas em relação à aplicabilidade da termocromia em estampas de camisetas, bem como mostrar as capacidades subjetivas de comunicação/expressão e de interatividade em produtos com essa tecnologia, que podem servir como auxílio para os designers em projetos inovadores. Neste sentido, foram propostos estudos experimentais de aplicação de estampas com tinta termocrômica em camisetas, que deram o sentido fundamental a esta dissertação, acrescentando conhecimento e abrindo espaço para novas pesquisas no âmbito interdisciplinar. Neste estudo de caso exploratório, foi possível concluir, que os métodos mostrados aqui são fatores importantes de inovação para o setor têxtil e de moda e que os testes produzidos provaram a necessidade de rigor técnico contido nas especificações técnicas do fornecedor. / This study aims to clarify some fundamental questions related to textile thermochromism in the application of t-shirt printing, namely the expressive power of prints and the use of thermochromism as a resource in surface design. The investigation brings historical data regarding the t-shirt as an object of design and fashion. In this context, the importance of technical clarification related to the performance of thermochromic ink is verified and a range of products utilized in this technique are presented. A number of innovative academic studies in this area are also presented. The main objectives of this study are to investigate new knowledge about the applicability of systems and techniques utilized in thermochromic t-shirt graphics and to demonstrate the subjective capacity of expression and interaction of products that utilize this technology, which can serve as an aid to designers in innovative projects. From this perspective, experimental tests in the application of thermochromic t-shirt printing were proposed, providing significance to this thesis, enhancing the knowledge in this field and promoting further interdisciplinary research. In this exploratory case study it was possible to conclude that the methods shown here represent important innovations in the textile and fashion sectors and that the tests demonstrated the necessity of technical rigor regarding manufacturers’ technical specifications.

abstract: Spider dragline silk is an outstanding biopolymer with a strength that exceeds steel by weight and a toughness greater than high-performance fibers like Kevlar. For this reason, structural and dynamic studies on the spider silk are of great importance for developing future biomaterials. The spider dragline silk comprises two silk proteins, Major ampullate Spidroin 1 and 2 (MaSp1 and 2), which are synthesized and stored in the major ampullate (MA) gland of spiders. The initial state of the silk proteins within Black Widow MA glands was probed with solution-state NMR spectroscopy. The conformation dependent chemical shifts information indicates that the silk proteins are unstructured and in random coil conformation. 15N relaxation parameters, T1, T2 and 15N-{1H} steady-state NOE were measured to probe the backbone dynamics for MA silk proteins. These measurements indicate fast sub-nanosecond timescale backbone dynamics for the repetitive core of spider MA proteins indicating that the silk proteins are unfolded, highly flexible random coils in the MA gland. The translational diffusion coefficients of the spider silk proteins within the MA gland were measured using 1H diffusion NMR at 1H sites from different amino acids. A phenomenon was observed where the measured diffusion coefficients decrease with an increase in the diffusion delay used. The mean displacement along the external magnetic field was found to be 0.35 μm and independent of the diffusion delay. The results indicate that the diffusion of silk protein was restricted due to intermolecular cross-linking with only segmental diffusion observable. To understand how a spider converts the unfolded protein spinning dope into a highly structured and oriented in the super fiber,the effect of acidification on spider silk assembly was investigated on native spidroins from the major ampullate (MA) gland fluid excised from Latrodectus hesperus (Black Widow) spiders. The in vitro spider silk assembly kinetics were monitored as a function of pH with a 13C solid-state Magic Angle Spinning (MAS) NMR approach. The results confirm the importance of acidic pH in the spider silk self-assembly process with observation of a sigmoidal nucleation-elongation kinetic profile. The rates of nucleation and elongation and the percentage of β-sheet structure in the grown fibers depend on pH. The secondary structure of the major ampullate silk from Peucetia viridians (Green Lynx) spiders was characterized by X-ray diffraction (XRD) and solid-state NMR spectroscopy. From XRD measurement, β-sheet nano-crystallites were observed that are highly oriented along the fiber axis with an orientational order of 0.980. Compare to the crystalline region, the amorphous region was found to be partially oriented with an orientational order of 0.887. Further, two dimensional 13C-13C through-space and through-bond solid-state NMR experiments provide structural analysis for the repetitive amino acid motifs in the silk proteins. The nano-crystallites are mainly alanine-rich β-sheet structures. The total percentage of crystalline region is determined to be 40.0±1.2 %. 18±1 % of alanine, 60±2 % glycine and 54±2 % serine are determined to be incorporated into helical conformations while 82±1 % of alanine, 40±3 % glycine and 46±2 % serine are in the β-sheet conformation. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2015

abstract: Nanomaterials have attracted considerable attention in recent research due to their wide applications in various fields such as material science, physical science, electrical engineering, and biomedical engineering. Researchers have developed many methods for synthesizing different types of nanostructures and have further applied them in various applications. However, in many cases, a molecular level understanding of nanoparticles and their associated surface chemistry is lacking investigation. Understanding the surface chemistry of nanomaterials is of great significance for obtaining a better understanding of the properties and functions of the nanomaterials. Nuclear magnetic resonance (NMR) spectroscopy can provide a familiar means of looking at the molecular structure of molecules bound to surfaces of nanomaterials as well as a method to determine the size of nanoparticles in solution. Here, a combination of NMR spectroscopic techniques including one- and two-dimensional NMR spectroscopies was used to investigate the surface chemistry and physical properties of some common nanomaterials, including for example, thiol-protected gold nanostructures and biomolecule-capped silica nanoparticles. Silk is a natural protein fiber that features unique properties such as excellent mechanical properties, biocompatibility, and non-linear optical properties. These appealing physical properties originate from the silk structure, and therefore, the structural analysis of silk is of great importance for revealing the mystery of these impressive properties and developing novel silk-based biomaterials as well. Here, solid-state NMR spectroscopy was used to elucidate the secondary structure of silk proteins in N. clavipes spider dragline silk and B. mori silkworm silk. It is found that the Gly-Gly-X (X=Leu, Tyr, Gln) motif in spider dragline silk is not in a β-sheet or α-helix structure and is very likely to be present in a disordered structure with evidence for 31-helix confirmation. In addition, the conformations of the Ala, Ser, and Tyr residues in silk fibroin of B. mori were investigated and it indicates that the Ala, Ser, and Tyr residues are all present in disordered structures in silk I (before spinning), while show different conformations in silk II (after spinning). Specifically, in silk II, the Ala and Tyr residues are present in both disordered structures and β-sheet structures, and the Ser residues are present primarily in β-sheet structures. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2017

abstract: Spider dragline silk is well known for its outstanding mechanical properties - a combination of strength and extensibility that makes it one of the toughest materials known. Two proteins, major ampullate spidroin 1 (MaSp1) and 2 (MaSp2), comprise dragline silk fibers. There has been considerable focus placed on understanding the source of spider silk's unique mechanical properties by investigating the protein composition, molecular structure and dynamics. Chemical compositional heterogeneity of spider silk fiber is critical to understand as it provides important information for the interactions between MaSp1 and MaSp2. Here, the amino acid composition of dragline silk protein was precisely determined using a solution-state nuclear magnetic resonance (NMR) approach on hydrolyzed silk fibers. In a similar fashion, solution-state NMR was applied to probe the "13"C/"15"N incorporation in silk, which is essential to understand for designing particular solid-state NMR methods for silk structural characterization. Solid-state NMR was used to elucidate silk protein molecular dynamics and the supercontraction mechanism. A "2"H-"13"C heteronuclear correlation (HETCOR) solid-state NMR technique was developed to extract site-specific "2"H quadrupole patterns and spin-lattice relaxation rates for understanding backbone and side-chain dynamics. Using this technique, molecular dynamics were determined for a number of repetitive motifs in silk proteins - Ala residing nanocrystalline &beta-sheet; domains, 3"1"-helical regions, and, Gly-Pro-Gly-XX &beta-turn; motifs. The protein backbone and side-chain dynamics of silk fibers in both dry and wet states reveal the impact of water on motifs with different secondary structures. Spider venom is comprised of a diverse range of molecules including salts, small organics, acylpolyamines, peptides and proteins. Neurotoxins are an important family of peptides in spider venom and have been shown to target and modulate various ion channels. The neurotoxins are Cys-rich and share an inhibitor Cys knot (ICK) fold. Here, the molecular structure of one G. rosea tarantula neurotoxin, GsAF2, was determined by solution-state NMR. In addition, the interaction between neurotoxins and model lipid bilayers was probed with solid-state NMR and negative-staining (NS) transmission electron microscopy (TEM). It is shown that the neurotoxins influence lipid bilayer assembly and morphology with the formation of nanodiscs, worm-like micelles and small vesicles. / Dissertation/Thesis / Ph.D. Chemistry 2014

abstract: An animal's ability to produce protein-based silk materials has evolved independently in many different arthropod lineages, satisfying various ecological necessities. However, regardless of their wide range of uses and their potential industrial and biomedical applications, advanced knowledge on the molecular structure of silk biopolymers is largely limited to those produced by spiders (order Araneae) and silkworms (order Lepidoptera). This thesis provides an in-depth molecular-level characterization of silk fibers produced by two vastly different insects: the caddisfly larvae (order Trichoptera) and the webspinner (order Embioptera). The molecular structure of caddisfly larval silk from the species <italic>Hesperophylax consimilis</italic> was characterized using solid-state nuclear magnetic resonance (ss-NMR) and Wide Angle X-ray Diffraction (WAXD) techniques. This insect, which typically dwells in freshwater riverbeds and streams, uses silk fibers as a strong and sticky nanoadhesive material to construct cocoons and cases out available debris. Conformation-sensitive <super>13</super>C chemical shifts and <super>31</super>P chemical shift anisotropy (CSA) information strongly support a unique protein motif in which phosphorylated serine- rich repeats (pSX)₄ complex with di- and trivalent cations to form rigid nanocrystalline &beta;-sheets. Additionally, it is illustrated through <super>31</super>P NMR and WAXD data that these nanocrystalline structures can be reversibly formed, and depend entirely on the presence of the stabilizing cations. Nanofiber silks produced by webspinners (order Embioptera) were also studied herein. This work addresses discrepancies in the literature regarding fiber diameters and tensile properties, revealing that the nanofibers are about 100 nm in diameter, and are stronger (around 500 MPa mean ultimate stress) than previous works suggested. Fourier-transform Infrared Spectroscopy (FT-IR), NMR and WAXD results find that approximately 70% of the highly repetitive glycine- and serine-rich protein core is composed of &beta;-sheet nanocrystalline structures. In addition, FT-IR and Gas-chromatography mass spectroscopy (GC-MS) data revealed a hydrophobic surface coating rich in long-chain lipids. The effect of this surface coating was studied with contact angle techniques; it is shown that the silk sheets are extremely hydrophobic, yet due to the microstructural and nanostructural details of the silk surface, are surprisingly adhesive to water. / Dissertation/Thesis / Doctoral Dissertation Biochemistry 2014

O estudo busca esclarecer pontos essenciais sobre o emprego da termocromia em têxteis por meio de sua aplicação em estampas em camisetas, respondendo questões sobre o poder expressivo destas e do uso da termocromia como recurso de qualificação em projetos de Design de Superfície. A pesquisa traz dados históricos da camiseta como objeto de design e moda. Nesse contexto verificou-se a relevância dos esclarecimentos técnicos sobre o funcionamento da tinta termocrômica, assim como apresenta-se no estudo uma gama de produtos que se utilizaram da aplicação desta técnica, além de estudos acadêmicos considerados inovadores nessa área de conhecimento. O objetivo principal do estudo é explorar novos conhecimentos sobre os sistemas e técnicas em relação à aplicabilidade da termocromia em estampas de camisetas, bem como mostrar as capacidades subjetivas de comunicação/expressão e de interatividade em produtos com essa tecnologia, que podem servir como auxílio para os designers em projetos inovadores. Neste sentido, foram propostos estudos experimentais de aplicação de estampas com tinta termocrômica em camisetas, que deram o sentido fundamental a esta dissertação, acrescentando conhecimento e abrindo espaço para novas pesquisas no âmbito interdisciplinar. Neste estudo de caso exploratório, foi possível concluir, que os métodos mostrados aqui são fatores importantes de inovação para o setor têxtil e de moda e que os testes produzidos provaram a necessidade de rigor técnico contido nas especificações técnicas do fornecedor. / This study aims to clarify some fundamental questions related to textile thermochromism in the application of t-shirt printing, namely the expressive power of prints and the use of thermochromism as a resource in surface design. The investigation brings historical data regarding the t-shirt as an object of design and fashion. In this context, the importance of technical clarification related to the performance of thermochromic ink is verified and a range of products utilized in this technique are presented. A number of innovative academic studies in this area are also presented. The main objectives of this study are to investigate new knowledge about the applicability of systems and techniques utilized in thermochromic t-shirt graphics and to demonstrate the subjective capacity of expression and interaction of products that utilize this technology, which can serve as an aid to designers in innovative projects. From this perspective, experimental tests in the application of thermochromic t-shirt printing were proposed, providing significance to this thesis, enhancing the knowledge in this field and promoting further interdisciplinary research. In this exploratory case study it was possible to conclude that the methods shown here represent important innovations in the textile and fashion sectors and that the tests demonstrated the necessity of technical rigor regarding manufacturers’ technical specifications.

Orientador: Marisa Masumi Beppu / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-12T12:02:05Z (GMT). No. of bitstreams: 1 Nogueira_GriniaMichelle_D.pdf: 10640071 bytes, checksum: 8b97ea00f684c6df573ea7e1ab6cc530 (MD5) Previous issue date: 2009 / Resumo: Hidrogéis e filmes de fibroína de seda foram preparados e caracterizados com o objetivo de avaliar sua potencial aplicação no campo de biomateriais. Hidrogéis foram obtidos durante a etapa de diálise da solução de fibroína de seda e suas propriedades físicas, químicas, citotoxicidade e potencial de calcificação in vitro foram determinados. Esses materiais apresentaram estrutura tridimensional porosa com resistência mecânica à compressão relativamente alta e grande potencial de calcificar in vitro, sendo possíveis candidatos à aplicação na área de regeneração óssea. Filmes de fibroína de seda com quitosana foram preparados utilizando-se a técnica "Layer-by-Layer". Com esta técnica, foi possível depositar filmes anisotrópicos, com fibras alinhadas na superfície de substratos de silício. Como os biopolímeros em estudo são conhecidamente biocompatíveis, o alinhamento de fibras na superfície do substrato poderia ser explorado como um meio de guiar a adesão e proliferação celular ou ainda agregar resistência mecânica a outros filmes poliméricos. Filmes de fibroína de seda foram também empregados para recobrir pericárdio bovino utilizado na fabricação de válvulas cardíacas. Amostras recobertas com fibroína de seda foram avaliadas quanto à sua propensão à calcificação in vitro e os filmes foram testados quanto a sua citotoxicidade e potencial de adesão e crescimento de células endoteliais. Os resultados indicaram que filmes de fibroína de seda não apresentam citotoxicidade, são compatíveis com células endoteliais e não induzem a calcificação do pericárdio bovino recoberto durante os testes in vitro. Assim, o recobrimento com fibroína de seda pode ser uma alternativa de tratamento do pericárdio bovino para funcionalização da sua superfície. Dos resultados apresentados, concluiu-se que tanto hidrogéis como filmes derivados de fibroína de seda podem ser aplicados no campo de biomateriais, sejam como matrizes para reconstituição óssea, ou filmes para recobrimento e funcionalização da superfície de materiais. / Abstract: Silk fibroin hydrogels and films were prepared and characterized in order to investigate their potential application in the biomaterials field. The hydrogels were obtained during the dialysis step and their physical and chemical characteristics, cell toxicity and compatibility and potential to calcify in vitro were investigated. Those materials presented a porous tridimensional structure, mechanical strength and ability to deposit calcium phosphate crystals during in vitro calcification tests; therefore, silk fibroin hydrogels can probably be used in the bone regeneration field. Silk fibroin films were obtained by using the Layer-by-Layer technique. Bidirectional alignment of silk fibroin fibers was designed by adjusting the substrate position during the dipping process. A potential application to films with alignment of fibers is to guide cell adhesion and proliferation, since the biopolymers used to build the films are known as biocompatible materials. Silk fibroin films were also used to coat bovine pericardium used to fabricate cardiac valves. The coated samples were characterized by in vitro calcification tests and biocompatibility of silk fibroin films was evaluated by citotoxicity tests and their ability to adhere and grow of endothelial cells. The results showed that silk fibroin films are biocompatible and do not induce calcification during in vitro calcification tests, being suitable to coatand functionalize bovine pericardium surface. From the presented results, it can be concluded that silk fibroin hydrogels and films are suitable materials to be explored in the biomaterials field, for bone regeneration or biomaterials surface coating. / Doutorado / Engenharia de Processos / Doutor em Engenharia Química