Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-03-13T13:58:54Z No. of bitstreams: 1 MariaSuerbenePaulinoPereira_DISSERT.pdf: 17360307 bytes, checksum: c6c4b86b42d455caf64863d2f08292fe (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-03-19T16:56:01Z (GMT) No. of bitstreams: 1 MariaSuerbenePaulinoPereira_DISSERT.pdf: 17360307 bytes, checksum: c6c4b86b42d455caf64863d2f08292fe (MD5) / Made available in DSpace on 2018-03-19T16:56:01Z (GMT). No. of bitstreams: 1 MariaSuerbenePaulinoPereira_DISSERT.pdf: 17360307 bytes, checksum: c6c4b86b42d455caf64863d2f08292fe (MD5) Previous issue date: 2017-07-18 / Trata este trabalho de uma interven??o pedag?gica para turmas de 9? ano do curso EJA, cuja pretens?o ? analisar, interpretar e investigar, na perspectiva da Literatura Comparada, procedimentos dial?gicos entre os contos Fita Verde no Cabelo, nova velha est?ria, e Herbarium, de Guimar?es Rosa e Lygia Fagundes Telles, respectivamente, dando-se ?nfase ? constru??o da imagem do sujeito-feminino nas obras em quest?o. Nesse estudo, busca-se, tamb?m, compreender a linguagem do conto, seus aspectos mais relevantes, configurados muitas vezes pela representa??o simb?lica, recurso recorrente nas hist?rias desses escritores. A escolha dessas duas obras e autores deu-se pela necessidade de se introduzir textos que tragam contribui??es significativas para a constru??o do ser humano como pessoa e cidad?o, levando o aluno a perceber que a literatura vai muito al?m de entretenimento. Seu conte?do expressa as nossas ang?stias, sentimentos e anseios, opini?es e contradi??es revelados atrav?s das muitas vozes presentes no texto. Em rela??o ao letramento liter?rio e ? proposta de aplica??o em sala de aula, bem como as reflex?es sobre o papel da literatura na forma??o leitora e cidad? do aluno e as rela??es dial?gicas presentes nos dois contos, toma-se como fundamenta??o te?rica o pensamento de Rildo Cosson, Candido, Cereja, Bakhtin, Coelho e outros. / This work is about a pedagogical intervention for 9th graders students of EJA (Young and adults course) whose intention is to analyze, ineterpret and investigate, from the perspective of Comparative Literature, dialogic procedures between the tales Fita Verde no Cabelo, nova velha est?ria, e Herbarium, from Guimar?es Rosa and Lygia Fagundes Telles, respectively, emphasizing the construction of the image of the female subject in the tales in question. In this study, we also try to understand the language of the stories, its most relevant aspects, often shaped by the symbolic representation, recurrent feature in the stories of these writers. The choice of these two works and authors was due to the need to introduce texts that bring significant contributions to the construction of the human being as a person and citizen, leading the student to realize that literature goes far beyond entertainment. Its content expresses our anxieties, feelings and longings, opinions and contradictions revealed through the many voices present in the text. In relation to literary literacy and the proposal of application in the classroom, as well as the reflections on the role of literature in the learner's and citizen's formation of the student and the dialogical relations present in the two stories, we take as theoretical foundation the thoughts of Rildo Cosson, Candido, Cereja, Bakhtin, Coelho and many others.

Made available in DSpace on 2018-08-02T00:02:56Z (GMT). No. of bitstreams: 1 tese_10759_LEANDRO PRATES FERREIRA DE ALMEIDA .pdf: 8649944 bytes, checksum: e7a2c275bfacd690ee0a5b517c44e443 (MD5) Previous issue date: 2017-02-24 / O estudo do contato roda-trilho tem ganhado importância na Engenharia Ferroviária, especialmente por trilho e roda representarem os segundo e terceiro maiores custos com materiais na ferrovia, ficando atrás somente dos gastos com combustível. Geralmente o fim de vida destes componentes se dá devido ao desgaste. As condições de contato variam de acordo com as particularidades de cada ferrovia, como carga, velocidade, traçado e materiais utilizados, entre outros. Com o objetivo de entender os mecanismos de desgaste existentes para as condições de contato típicas da Estrada de Ferro Vitória a Minas, foram realizados ensaios de desgaste por deslizamento na configuração pino-disco, sem lubrificação, com velocidade de deslizamento variável e carga normal constante. Os pinos, de extremidade esférica, foram fabricados com material do trilho convencional da EFVM aço perlítico com dureza superficial de 370 Brinell e os discos foram fabricados com material de rodas fundidas e forjadas da classe C da norma AAR. O volume desgastado dos pinos foi calculado com base no diâmetro da calota de desgaste. Já nos discos, o volume desgastado foi obtido por perfilometria 3D. Os mecanismos de desgaste foram analisados com auxílio de um microscópio estereoscópico e de um microscópio eletrônico de varredura. Os resultados indicam um aumento no coeficiente de atrito nos ensaios à velocidade de 0,9 m/s µ aproximadamente 0,8 quando comparado com os valores obtidos à velocidade de 0,1 m/s, onde µ ficou entre 0,5 e 0,6. Já a severidade do desgaste, tanto dos pinos quanto dos discos, foi maior nos ensaios realizados com velocidade de deslizamento de 0,1 m/s. Comparando os diferentes materiais dos discos, o desgaste de pinos e discos foi consideravelmente maior nos sistemas com rodas forjadas. Os mecanismos de desgaste observados foram predominantemente de natureza plástica, com ocorrência de sulcos plásticos e adesão de materiais oxidados na superfície de pinos e discos. Palavras-chave: roda, trilho, ferrovia, desgaste por deslizamento, pino, disco, mecanismos de desgaste.

Undressing Cherubino: Reassessing Gender and Sexuality in Mozart’s Le nozze di Figaro Although Le nozze di Figaro is one of Mozart’s most celebrated operas, we have not yet understood one crucial element. On the surface of the drama, the opera seems to be about class disruption: the Count is the head of the household, but it is his servants who run it. This plot is made evident to the audience, and it is the message that most critics draw from the work. However, there may be a second meaning below the surface that is, in fact, more subversive than the overt one. While class structures are questioned in the foreground, another more hidden narrative explores alternate depictions of femininity and sexuality. This covert meaning is arguably embodied in Cherubino. This character is portrayed as an adolescent boy despite the fact that the role calls for a female singer. Cherubino is understood to be male, and functions as one in the drama, but, as I will suggest, may in fact be conceived as female. As a pagegirl raging with sexual love for all the women in the palace, Cherubino may be seen embodying a prototype of femininity that is contrary to the heterosexual norms of the overt narrative. The first chapter of this thesis examines how both Pierre-Augustin Beaumarchais’ play Le mariage de Figaro and Mozart and Da Ponte’s operatic adaptation could point towards alternate depictions of women. The following two chapters survey the various ways an alternate gender identity for Cherubino can be expressed through features of the libretto (chapter 2) and the score (chapter 3). Drawing from my experience of performing Cherubino, the fourth and final chapter assesses the findings of the previous two and shows that while elements of the text and music may have characteristics that can be assigned gender attributes, neither can intrinsically embody masculinity or femininity. With this finding comes the understanding that who and what a character is is marked not by the outlines of libretto and score but by acts of musical performance.

Over the past decades, numerous studies shown curcumin, a dietary compound derived from turmeric, has a variety of health-promoting actions, such as anti-oxidant, anti-microbial, anti-inflammatory, and anti-cancer effects, making curcumin the most promising dietary compound for disease prevention. However, the underlying mechanisms by which curcumin has these health-promoting effects are not well understood. A better understanding of the molecular mechanism of curcumin could help to develop novel strategies to reduce the risks of some human diseases. Protein thiols play important roles in cell signaling, and recent studies showed that curcumin could covalently react with protein thiols, supporting that curcumin-protein interactions could contribute to the health-promoting effects of curcumin. However, the curcumin-protein interactions are under-studied. Notably, it remains unknown whether oral intake of curcumin could covalently interact with protein in vivo. In this project, we synthesized a click chemistry probe of curcumin (Di-Cur), and used this probe to characterize curcumin-protein interactions both in vitro and in vivo using a click chemistry-based imaging approach. Our results demonstrate that orally administrated curcumin could form curcumin-protein adducts in specific tissues of the mice, which may contribute to the potent biological effects and poor pharmacokinetics of curcumin.

This thesis examines how the kinetic properties of pair-produced Higgs bosons depend on whether the process is mediated by particles in the Standard Model or a simplified supersymmetric model. The analysis is based on simulated data made using MadGraph. The examination within this thesis is split into two parts, one performed on the output of MadGraph (parton level) and the second performed on the output of a simplified simulation of the ATLAS detector response (reconstruction level). The first part also contains a section showing that the supersymmetric model results are consistent with the Standard Model results in cases where no supersymmetric particles are present in the di-Higgs production and decay, and a section detailing the minor differences in kinematics of the Higgs bosons depending on the mass of the supersymmetric partner of the top quark. The second part of the thesis covers the decay of the Higgs boson into bottom and anti-bottom quarks, and includes a section showing that there is no difference if the decay is done using the MadSpin module or the Pythia module for MadGraph, before exploring the kinematics of the jets produced. Both when studying Higgs bosons at the parton level and when studying b-jets at the reconstruction level, it is found that there are clear differences in the kinematics between the Standard Model and the supersymmetric model. At both levels, a neural network has been designed, trained and tested. For the parton level neural network 59 % of all events are classified correctly, while at the reconstruction level 51 % of all events are classified correctly. These neural network results show that it is possible to train a neural network to learn on data like this, and that with enough di-Higgs events detected, their kinematic properties could be used to indirectly infer the presence of physics beyond the Standard Model.

Distillation technology involves capital- and energy-intensive processes for light olefin/paraffin separation. Global demand for propylene has already exceeded 110 million tons per year. Therefore, distillation processes used for the separation of C3H6/C3H8 should be replaced or debottlenecked with more efficient and cost-effective technology. In the last three decades, membrane-based gas separation processes have successfully emerged, thus competing with conventional separation processes. Membranes potentially offer lower capital investment and operation cost than distillation columns. In this study, the use of advanced membrane materials for C3H6/C3H8 separation was investigated. Three novel triptycene-based polyimides were synthesized by Dr. Bader Ghanem from one diamine monomer, namely 2,6-dihydroxy-3,7-diaminotriptycene (DTA1-OH), and three dianhydride monomers, (i) non-substituted triptycene tetracarboxylic dianhydride (TDA), (ii) 9,10-dimethyltriptycene tetracarboxylic dianhydride (TDA1) and (iii) 9,10-iso-propyltriptycene tetracarboxylic dianhydride (TDAi3). It is important to note that polyimide membranes based on triptycene dianhydrides and triptycene diamines have never been reported in the literature before. Pure-gas permeability coefficients of He, H2, N2, O2, CO2, CH4, C3H6, and C3H8 were determined at 2 bar and 35 °C. Furthermore, C3H6 and C3H8 gas sorption isotherms were measured by gravimetric techniques, and experimental data were collected up to 7 bar at 35 °C. TDA-DAT1-OH, TDA1-DAT1-OH, TDAi3-DAT1-OH exhibited C3H6 permeability of 12.1, 16.6, and 5.64 Barrer with pure-gas C3H6/C3H8 selectivity of 35.7, 29.6, and 32.8 respectively. These properties exceeded the 2003 pure-gas upper bound for C3H6/C3H8. The BET surface area increased in the order of TDA-DAT1-OH (437 m2/g) < TDAi3-DAT1-OH (467 m2/g) < TDA1-DAT1-OH (557 m2/g). The frecational free volume (FFV) increased in the order of TDAi3-DAT1-OH (0.25) < TDA-DAT1-OH (0.28) < TDA1-DAT1-OH (0.30). TDA1-DAT1-OH (109 μm) showed less and slower physical aging than TDA-DAT1-OH (94 μm) after 60 days, where the O2 and CO2 permeability of both polyimides decreased by about 40% and 69%, respectively. After 30 days, TDAi3-DAT1-OH displayed the highest selectivity gain relative to its counterparts and exceeded the 2008 upper bound for CO2/CH4. TDA1-DAT1-OH exhibited 7-fold higher C3H6 permeability coupled with almost 3-fold higher C3H6/C3H8 selectivity relative to a previously reported commercial polyphenylene oxide (PPO) membrane.

Cyclic-di-GMP, a common bacterial second messenger, has been thought to help develop virulence and biofilms in bacteria, most specifically in Salmonella Typhimurium. By being able to dysregulate cyclic-di-GMP production, virulence may be better combatted. STM1987, an L-arginine-responsive diguanylate cyclase with a periplasmic sensory domain, dimerizes and generates the bacterial second messenger cyclic-di-GMP in response to the amino acid L-arginine in a pathway that also requires the periplasmic L-arginine-binding protein ArtI. Their biochemical responses to L-arginine and when they dimerize could help clarify this pathway, so I sought to develop a periplasmic dimerization sensor to better monitor these biochemical interactions. Similar to STM1987, the ToxR transcriptional regulator from Vibrio cholera is also activated by dimerization. By switching out the periplasmic domain of ToxR for the periplasmic regions of interest, I can better evaluate the cyclic-di-GMP response to L-arginine. This research aims to find the specific responses in this pathway to be able to use this in combatting bacterial virulence. I was able to successfully show that the STM1987 periplasmic domain dimerizes in response to L-arginine, providing an important insight into this signaling pathway.

Abstract Acinetobacter baumannii is a prevalent nosocomial where infections are typically secondary infections to patients that already have an infection or other source of being immunocompromised. Like many other infectious bacteria, A. baumannii is increasingly considered a multi-drug resistant pathogen. This eliminates the ability to treat A. baumannii infections with traditional antibiotics, hence the need for another method of treating A. baumannii. This research study was designed to find a way to affect the survival of A. baumannii such that it can be applied to a hospital setting to prevent further infections to immunocompromised patients. One mechanism potentially used by A. baumannii to persist on hospital surfaces is through the use of the bacterial second messenger cyclic-di-GMP (c-di-GMP). This nucleotide signal is regulated in response to environmental conditions, and then activates c-di-GMP-binding proteins that induce phenotypic changes. I hypothesized that by deleting these c-di-GMP-binding proteins that it will produce measurable differences in phenotype like biofilm formation, motility, and desiccation survival. Reducing phenotypes such as these may alter A. baumannii’s ability to persist on hospital surfaces, and potentially lead to future surface eradication. A. baumannii encodes two potential c-di-GMP-binding proteins of particular interest, one that contains a sole PilZ domain and another that pairs a PilZ domain with a hydrolase domain. PilZ domains bind c-di-GMP within a conserved binding site, regulating the conformational structure of the protein, and are named for the first studied PilZ domain within the pilus-associated PilZ protein. Pili are used in pilus-mediated motility and surface attachment, and they are A. baumannii’s primary method of motility due to not having flagellum. I hypothesized that by removing these c-di-GMP-binding proteins, I would interrupt the c-di-GMP signaling that might regulate motility. I am testing two A. baumannii strains: 5075, a recent military hospital isolate and 17978, an older lab strain. A notable difference between these two strains is that 5075 demonstrates twitching motility where it utilizes type IV pili, but 17978 demonstrates swarming motility that has unknown mechanisms. Both c-di-GMP-binding proteins were tested for their role in twitching or swarming motility of the respective strains. I found that swarming motility of 17978 is regulated by both c-di-GMP-binding proteins. While I am still generating the deletion strain for the c-di-GMP-binding hydrolase enzyme, the sole PilZ domain protein is also required for twitching motility in the 5075 strain. These results suggest c-di-GMP regulates both forms of motility in A. baumannii. Future plans include determining the role of the c-di-GMP-binding hydrolase enzyme in twitching motility and identifying the role that these proteins play through binding of c-di-GMP.

Acinetobacter baumannii is an increasingly multidrug-resistant Gram-negative bacterial pathogen and contributes to many hospital-acquired infections. Discovering new treatments against Acinetobacter baumannii infections is necessary as the pathogen adapts to the antimicrobials prescribed by physicians. Cyclic di-GMP (c-di-GMP), a bacterial second messenger, can regulate various phenotypes including biofilm formation, desiccation tolerance, motility, etc.; many of these phenotypes may help A. baumannii better survive a hospital environment, such as dryness on hospital surfaces. Up to twelve c-di-GMP modulating enzymes (CMEs) and two c-di-GMP binding proteins are predicted to be encoded by this pathogen. Diguanylate cyclases (DGCs) produce c-di-GMP, whereas phosphodiesterases (PDEs) degrade c-di-GMP. More c-di-GMP that can bind to its binding proteins means more biofilm formation and less motility. Of the eleven CMEs, 7 are DGCs, 2 are PDEs, and 3 encode both domains (DGCs/PDEs). I hypothesized that biofilm formation, desiccation tolerance, and motility were controlled by c-di-GMP and that we could target these parts of the c-di-GMP signaling network for new treatments. If we disrupt these genes, then we should see a reduction in the regulatory effects of these phenotypes. In this investigation, we generated mutants with a single gene knockout or transposon mutagenesis in two different A. baumannii strains: 17978, a historical laboratory strain that exhibits swarming motility and AB5075, a recent clinical isolate that exhibits twitching motility. To test biofilm formation, we let the mutants grow to their maximum concentration in 96-well plates, stained the plates with crystal violet, and quantified the crystal violet that stained the biofilm. To test for motility, a LB agar plate was stabbed to the plastic surface or dropped on the agar surface with diluted culture to determine the presence of twitching or swarming motility, respectively. To test for desiccation tolerance, we washed the cultures in distilled water to rid the sample of any salt, serially diluted the samples in solution, and plated them out onto LB agar plates. Bacterial counts were quantified before and after desiccation to determine survival of each mutant. From these experiments, 6 DGCs, 1 PDE, and 2 DGCs/PDEs were shown to regulate biofilm formation in AB5075. Furthermore, a PDE and a DGC/PDE were shown to regulate twitching motility in AB5075, while a single DGC was required for tolerating dryness. In strain 17978, we have found a PDE and 4 DGCs that are necessary for swarming motility and are currently conducting biofilm and desiccation tolerance assays. So far, we’ve identified a role for c-di-GMP in A. baumannii biofilm formation, motility, and desiccation survival. Inhibiting the regulation of these pathways could produce novel mechanisms to combat this pathogen in the hospital environment.

Methylglyoxal (MGO) is a highly reactive dicarbonyl compound, formed as a metabolite from nonenzymatic and enzymatic reactions and is the leading precursor of advanced glycation end products (AGEs). AGEs contribute to ageing, type 2 diabetes mellitus (T2DM), and diabetes-related complications. However, MGO also has beneficial antibacterial activity and is the bioactive ingredient of medicinal honeys such as Manuka. Flavonoids are a group of phytochemicals that are powerful antioxidants. Polyphenols including flavonoids have been reported to trap MGO, forming adducts thereby preventing AGE formation. However, there is little to no information on the effect of adduct formation on the antioxidant properties of flavonoids and the antibacterial activity of MGO. In this study, catechin (CAT), chrysin (CHRY) and naringenin (NAR) at 0.1 mM and mixtures of each flavonoid with MGO (1:1) and (1:2) were evaluated for antioxidant and antibacterial activity. Antioxidant activity/capacity were evaluated with the total polyphenolic content (TPC), total flavonoid content (TFC), Trolox equivalent antioxidant capacity (TEAC) and the oxygen radical absorbent capacity (ORAC) assays. The bovine serum albumin (BSA)/MGO model was used to evaluate the effect on glycation. The 2’, 7’-dichlorofluorescein diacetate (DCFH-DA) assay with the L929 cell line was used to evaluate cellular antioxidant activity. Cytotoxicity was determined in the L929 cell line using the crystal violet (CV) and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) tetrazolium (MTT) assays. Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) were used to determine antibacterial activity using the microbroth-dilution assay and subsequent changes to morphology were evaluated using scanning electron microscopy (SEM). A reduction in antioxidant content was observed for: CHRY (TPC), CAT and NAR (TFC) and in antioxidant activity for: CHRY (TEAC) and CAT (ORAC), when combined with MGO. Overall most of the antioxidant activity of the flavonoids was not affected by the addition of MGO. In the presence of BSA and MGO, all flavonoid:MGO combinations reduced formation of AGEs except NAR in combination with MGO. All flavonoids alone and in combinations did not cause cellular oxidative damage while MGO and AAPH induced increased cellular damage indicating that MGO via AGE formation makes cells more sensitive to the effects of oxidants that form radicals. Only CAT reduced the oxidative effects of MGO/AAPH. For all combinations there was no effect on cell number, although cell viability was significantly reduced for CHRY and its combinations and for NAR and NAR:MGO1. Flavonoids at 0.1 mM CAT, CHRY and NAR had no antibacterial activity against E. coli while inhibition was observed only with NAR against B. subtilis. MGO at 0.1 and 0.2 mM inhibited bacterial growth while in combination the antibacterial activity was significantly reduced. MGO as well as NAR caused major changes to bacteria morphology. In combination, the antibacterial activity of MGO was reduced, and ultrastructure changes associated with toxicity was also observed in most groups. In conclusion, flavonoids do trap MGO and this effect does not significantly alter flavonoid antioxidant activity. However, the antibacterial activity of MGO is reduced. Future studies should focus on the chemistry and the effects involved and should include dosage dependent studies. / Dissertation (MSc)--University of Pretoria, 2019. / Anatomy / MSc / Unrestricted