In this thesis different aspects of calcium-aluminate (CA) as biomaterial are presented. Calcium aluminate is a chemically bonded ceramic with inherent properties making it suitable for use as biomaterial in some applications. In this thesis the emphasis is put on the basic chemical, physical and mechanical properties that may be achieved using the CA system as well as synthesis of the CA raw material. The basis for using CA in any application is the synthesis of the raw material. Different synthesis routes for producing CA are presented with focus on high temperature routes and the micro-structural and phase development during synthesis. As a base for further understanding of the CA properties a thorough outline of the reaction chemistry for CA is presented also including a description of how the reactions may be controlled and how formulations can be designed. The surface reactions of CA when subjected to simulated body fluid showed that CA is in vitro bioactive. An in vivo study in teeth also indicates that CA produces apatite at the tooth material interface. Dental materials are subjected to a harsh environment in the mouth with high mechanical forces, erosion and thermal changes. Also the demands on precise handling characteristics are high. For these reasons the in vitro evaluation of physical and mechanical properties are important. In this work several mechanical and physical properties of Ca-based formulations for dental applications has been tested using different methods. Some attention is also put on the specific characteristics of CA and the difficulties that arise when new material classes needs to be tested according to consensus standard methods. Finally studies on a CA-based formulation intended for Vertebroplasty is presented. The studies include basic mechanical properties as well as testing the material in an in vitro model utilising synthetic cancellous bone.

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 6 uppsatser.

Orientador: Devaney Ribeiro do Carmo / Banca: Newton Luiz Dias Filho / Banca: Regina Massako Takeuchi / Resumo: O presente trabalho apresenta a preparação de um silsesquioxano nanoestruturado, o cloropropilsilsesquioxano (S) que foi organofuncionalizado com os seguintes agentes modificadores: 4-amino-3-hidrazinico-5-mercapto-1,2,4-triazol (Purpald®) e o 4-amino-5-4(piridil)-4H-1,2,4-triazol-3-tiol (APTT), os materiais obtidos dessa funcionalização foram descritos como SP e SA, respectivamente. Os materiais SP e SA foram caracterizados por diversas técnicas espectroscópicas: Espectroscopia na região do infravermelho (FT-IR), Ressonância magnética nuclear 29Si e 13C no estado sólido (RMN), Difração de Raios- X (DRX), Espectroscopia de Energia Dispersiva de Raios X (EDX), Termogravimetria e Análise Térmica Diferencial (TG - DTA). Após a devida caracterização, realizaram-se estudos de adsorção de íons metálicos (Cu2+, Cd2+ e Ni2+) nos sítios ativos do SA, porém, curiosamente não se observou a mesma capacidade de sorção pelo SP. Diferentes meios foram estudados no processo de adsorção dos íons metálicos supracitados: aquoso, etanólico 99% e etanólico 42%, determinando-se o tempo de equilíbrio de adsorção, que para ambos os meios e metais esse tempo máximo foi em média 35 min. Determinado o tempo de equilíbrio de adsorção dos íons metálicos em cada sistema, determinou-se a capacidade específica de sorção (Nfmax) através de isotermas de adsorção. Para o Cu2+, os valores de Nf foram: meio aquoso (3,09 × 10-4 mol g-1), etanólico 42% (1,03 × 10-4 mol g-1) e etanólico 99% (1,86 × 10-4 mol g-1), com concentrações de íons Cu2+ variando de 1,74 a 29,64 mol L-1. Os valores encontrados para o Ni2+ foram: em meio aquoso (2,11 × 10-4 mol g-1), etanólico 42% (0,97 × 10-4 mol g-1) e etanólico 99% (1,05 × 10-4 mol g-1), com concentrações de íons Ni2+ variando de 2,25 a 33,18 mol L-1. Para os íons cádmio não foram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work presents the preparation of a nanostructured silsesquioxane, the cloropropilsilsesquioxano (S) that was organofunctionalised with the following modifying agents: 4-amino-3-hydrazino 5 - mercapto 1,2,4 triazole (Purpald ®) and 4- amino-5-4 (pyridyl)-4H-1,2,4-triazole-3-thiol (APTT), the materials obtained of the functionalization were described as SP and SA, respectively. The materials SA and SP were characterized by various spectroscopic techniques such as spectroscopy in the region of infrared (FTIR), nuclear magnetic resonance 29Si and 13C solid-state (NMR), X-ray diffraction (XRD), Energy Dispersive Spectroscopy Rays (EDS), Thermogravimetry and Differential Thermal Analysis (TG - DTA). After proper characterization, were carried studies on adsorption of metallic ions such as Cu2+, Ni2+ and Cd2+ in the active sites of SA, but curiously did not observe the same sorption capacity of the SP. Different methods were studied in the adsorption of metal ions above: aqueous, 99% ethanolic and 42% ethanolic, determining the adsorption equilibrium time, which for both means and metals the maximum time averaged 35 min. After determining the adsorption equilibrium time of metal ions in each system, we determined the specific sorption capacity (Nfmax) through adsorption isotherms. For Cu2+, the values of Nf were: aqueous solution (3.09 × 10-4 mol g-1), 42% ethanolic (1.03 × 10-4 mol g-1) and 99% ethanolic (1.86 × 10-4 mol g-1), with Cu2 + ion concentrations ranging from 1.74 to 29.64 mol L-1. The values obtained for the Ni2+ were: aqueous solution (2.11 × 10-4 mol g-1), 42% ethanolic (0.97 × 10-4 mol g-1) and 99% ethanolic (1.05 × 10-4 mol g-1), with Ni2 + ion concentrations ranging from 2.25 to 33.18 mol L-1. For the cadmium ions were not observed saturation of adsorption sites in the concentration range studied, not getting the maximum... (Summary complete electronic access click below) / Mestre

Soybeans are among seeds the common plant foods that contains high protein contents and high oil. The protein provides about 35 to 38 percent of the seeds calories compared to around 20 to 30 percent in other legumes and many animal products. The quality of soy protein is notable and approaches the quality of meat and milk. Unlike many other good sources of protein, soybeans are low in saturated fat and are cholesterol-free. Its proteins provide all the important amino acids, most the amounts needed by humans (NSRL, 2010). As the most consumed vegetable oil in the world, soybean oil has been used substantially in the food industry (Soystats, 2010). Its utilization is determined by its fatty acid composition, with commodity soybean oil typically 13% palmatic acid (16:0), 4% stearic acid (18:0), 20% oleic acid (18:1), 55% linoleic acid (18:2), and 8% linolenic acid (18:3). The change of fatty acid profiles to improve soybean oil quality has been a long time goal of many researchers throughout the world. Biodiesel is an up and coming trend in energy production. Breeding effort can be undertaken in order to produce a higher energy profile soybean oil. Using ethyl-methanesulfonate (EMS) mutagenesis effects on DNA, significant changes to the genes and gene network underlying the protein and oil profile can be achieved. These changes are hard to accomplish using standard breeding techniques. In addition, high amount of linolenic and stearic acid are very important for fuel and biodiesel production, but are not good for food production due to the fact that such oil is oxidized easily and the food goes rancid quickly. However, soybean oil with elevated amount of oleic acid is desirable for food, because this monounsaturated fatty acid improves the nutrition and oxidative stability of soybean oil compared to other oils. In order to improve the quality of soybean oil and processed foods, chemically mutagenized soybeans have been developed in this project. Seeds harvested from individual M3 and M4 plants (from 2 successive years 2012 and 2013) were analyzed for protein content, oil composition, and content. Moreover, seven phenotypic traits including oil analysis (stearic, palmitic, oleic, linolenic and linoleic), seed protein content, weight of the seeds (High yield), seeds color, stem length, germination rates, and branch architecture were collected and analyzed in this project of soybean `Forrest' mutagenized population. The result of this research showed that there were 25 significantly different lines (p< 0.05) compare to the wild type, which is useful for developing mutants with altered oil and fatty acid compositions in soybean.

Made available in DSpace on 2014-06-11T19:35:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-16Bitstream added on 2014-06-13T20:06:20Z : No. of bitstreams: 1 silva_rag_dr_araiq.pdf: 7974654 bytes, checksum: 26e0535c042c3672a9774fa309965a35 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho a cinética de decomposição da fase martensítica na liga Cu-10%Al com adições de 4, 6, 8 e 10%Ag foi estudada usando calorimetria exploratória diferencial (DSC), análise térmica diferencial (DTA), termodilatometria (TD), microscopia óptica (MO), microscopia eletrônica de varredura (MEV), difratometria de raios X (DRX), análise por dispersão de energias de raios X (EDX), medidas de variação da microdureza com a temperatura de têmpera e o tempo de envelhecimento e medidas de tensão-deformação. Os resultados obtidos indicaram a presença de uma etapa intermediária de reação nas ligas com 4 a 8%Ag, no intervalo de temperaturas de 200 a 300 oC, e essa etapa foi atribuída ao consumo da fase α desordenada. A presença da prata retardou a reação de decomposição eutetóide e intensificou o efeito de estabilização da fase martensítica no intervalo de temperatura e tempo considerados nesse estudo. Esse efeito de estabilização foi atribuído à redistribuição dos átomos de Ag como defeitos de estrutura, aumento do número de pares Cu-Al devido à interação Ag-Al e à redistribuição de átomos de Al ao redor de um átomo de Cu na sub-rede do cristal martensítico. Todos esses efeitos combinados diminuem a energia livre da fase martensítica e contribuem para o aumento da temperatura da transformação reversa. Para as ligas Cu-10%Al com e sem adições de prata a seqüência de reações durante o envelhecimento das amostras é composta das seguintes etapas: consumo da fase α seguida do ordenamento da martensita. A velocidade da reação de consumo da fase α depende da concentração de prata e uma mudança considerável na velocidade da reação de ordenamento da martensita é observada apenas para a liga com 10%Ag. Os valores das energias de ativação para os processos indicaram que a reação (α + β’)→β’ é a etapa dominante... / In this work, the kinetics of martensitic phase decomposition in the Cu-10wt.%Al alloy with additions of 4, 6, 8 and 10 wt.%Ag was studied using differential scanning calorimetry (DSC), differential thermal analysis (DTA), thermodilatometry (TD), optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffractometry (XRD), energy dispersive X-ray analysis (EDX), microhardness changes measurements with temperature and time and stress-strain measurements. The results indicated the presence of an intermediate reaction step for alloys with Ag additions up to 8wt.% in the temperature range between 200 and 300 oC, attributed to the consumption of the disordered α phase. The presence of Ag retarded the eutectoid decomposition reaction and enhanced the stabilization of the martensitic phase, in the time and temperature ranges considered. This stabilization effect was attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and to the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal. The combination of these effects decreases the martensitic phase free energy and increases the reverse transformation temperature. The proposed reactions sequence for the aging of Cu-10wt.%Al alloy with and without Ag additions is the consumption of the α phase followed by the martensitic phase ordering. The rate of the α phase consumption reaction depends on the Ag concentration and a remarkable change in the martensitic phase ordering reaction rate is only observed for the addition of 10wt.%Ag. The obtained activation energy values indicated that the (α + β’)→β’ reaction, assisted by quenched-in vacancies migration, is the dominant step.

Orientadores: Lauro Tatsuo Kubota, Marilia Oliveira Fonseca Goulart / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-13T21:41:20Z (GMT). No. of bitstreams: 1 Lima_PhabyannoRodrigues_D.pdf: 3618536 bytes, checksum: e30e8edf8ae8a08c57fdb0a003e8b6fd (MD5) Previous issue date: 2009 / Resumo: Neste trabalho descreve-se o desenvolvimento de sensores amperométricos a base de um simples eletrodo de pasta de carbono modificado com um novo mediador redox, a 4-nitroftalonitrila (4-NO2FN), para a determinação de alguns antioxidantes de relevância biológica [L-cisteína (L-CySH), L-glutationa (L-GSH), ácido L-ascórbico (L-AscH2), ácido úrico (AU) e nicotinamida adenina dinucleotídeo (forma reduzida) (NADH)]. Com este propósito, inicialmente, a 4-NO2FN foi ativada in situ, gerando o par redox nitroso/hidroxilamina (4-NOFN/4- NHOHFN) estável na superfície eletródica, o qual apresentou atividade electrocatalítica na oxidação dos analitos estudados. As técnicas empregadas para a realização deste trabalho foram voltametria cíclica e cronoamperometria, as quais foram utilizadas para estudar o comportamento dos eletrodos modificados, para otimização dos parâmetros experimentais, obtenção dos parâmetros cinéticos e caracterização analítica dos sensores. Além disso, os estudos hidrodinâmicos e cronoamperométricos foram realizados com o objetivo de se obter maiores informações sobre os processos de oxidação entre L-AscH2, NADH e os eletrodos modificados. Assim, por meio dos gráficos e equações de Koutech- Levich e Cottrell foi possível obter os valores para o coeficiente de difusão (D) e constante de velocidade da reação (kobs) para L-AscH2 e NADH. Os valores do D e de kobs, determinados para L-AscH2 e NADH, foram de 9,0x10 cm s e 2,4x10 cms, 6,0x10 molL s e 1,0x10 molL s, respectivamente. O aumento na velocidade de reação, tanto para o L-AscH2 quanto para o NADH, foi atribuído à eficiente transferência de elétrons entre estas espécies e o par redox 4-NOFN/4-NHOHFN eletrogerado in situ. Sob condições otimizadas, o sensor amperométrico apresentou uma faixa de resposta linear (mmol L), limite de detecção (mmol L), quantificação (mmol L) e sensibilidade (nA L mmol) para L-CySH (a), L-GSH (b), L-AscH2 (c), AU (d) e NADH (e), os quais apresentaram os valores de (a) 0,8-13,2, 0,25, 0,8, 37,0; (b) 8,0-83,0, 2,7, 8,0, 54,0; (c)5,0-120,0, 1,6, 5,5, 108,0; (d) 5,0- 120,0, 1,3, 4,5, 121,6 e (e) 0,8-8,5, 0,25, 0,82, 500,0, respectivamente. Após a aplicação destes sensores em amostras de interesse, estudos de adição e recuperação dos analitos foram realizados para avaliar a exatidão dos métodos e verificou-se que foi possível uma percentagem de recuperação entre 98,5 e 102,0% para L-CySH, L-GSH, L-AscH2 e AU / Abstract: In this work, the development of amperometric sensors based on a simple carbon paste electrode modified with a new redox ¿mediator¿, 4- nitrophthalonitrile (4-NO2PH), for quantification of some antioxidants of biological relevance (L-cystein (L-CySH), L-glutathione (L-GSH), L-ascorbic acid (L-AscH2), uric acid (UA) and b-nicotinamide adenine dinucleotide (NADH)), is described. For this purpose, initially, 4-NO2PH was activated in situ, generating a stable redox-active nitroso/hydroxylamine system (4- NOPH/4-NHOHPH) on the electrodic surface, which presented electrocatalytic activity towards the oxidation of studied analytes. The techniques used in this work were cyclic voltammetry and cronoamperometry, to study the behavior of the modified electrodes, for the experimental parameters optimization, for the attainment of the kinetic parameters and analytical characterization of the sensors. Hydrodynamic and cronoamperometric studies were carried out with the aim to get information on the reduction processes and oxidation of L-AscH2 and NADH, respectively, on the modified electrodes. Through the Koutech-Levich and Cotrell plots it was possible to obtain the values for the diffusion coefficient (D) and kinetic constant of the reaction (kobs) for the analytes in study. The values of the diffusion coefficient and kobs, determined for L-AscH2 and NADH were 9,0x10 cm s and 2,4x10 cms, 6,0x10 molL s and 1,0x10 molL s, respectively. The increase of the reaction rate for L-AscH2 and NADH was attributed to the efficient electron transfer between the studied species and immobilized electroactive species on the surface of the carbon paste electrode. After optimizing conditions, the sensor provided a linear response range (mmol L), limit of detection (LOD) (mmol L), limit of quantification (LOQ) (mmol L) and sensitivity (nA L mmol) for L-CySH (a), L-GSH (b), L-AscH2 (c), UA (d) e NADH (e) of (a) 0.8-13.2, 0.25, 0.8, 37.0; (b) 8.0-83.0, 2.7, 8.0, 54.0; (c)5.0-120.0, 1.6, 5.5, 108.0; (d) 5.0-120.0, 1.3, 4.5, 121.6 and (e) 0.8- 8.5, 0.25, 0.82, 500.0, respectively. After the application of these sensors in samples of interest, studies of addition and recovery of the analytes were carried out to evaluate the error of the methods and it was verified recovery percentages between 98.5 and 102.0% for L-CySH, L-GSH, L-AscH2 and AU, were obtained / Doutorado / Quimica Analitica / Doutor em Ciências

O presente trabalho descreve o preparo, a caracterização e o uso de eletrodo modificado com polímero de azul de metileno (PMB) imobilizado sobre a superfície de eletrodo de carbono vítreo (GCE-PMB) na análise do herbicida glifosato. O método utilizado para a preparação dos filmes do PMB foi a eletropolimerização. Os filmes preparados por este método apresentam características diferenciadas tais como robustez, estabilidade e propriedade redox satisfatória. As condições experimentais otimizadas foram a velocidade de varredura (50 mV s-1), o intervalo de potencial (-0,4 a +1,2 V), o número de ciclos (30) e o pH da solução do eletrólito suporte (pH 8). A solução de eletrólito suporte foi preparada a partir das soluções de tampão fosfato (0,05 mol L-1) e NaNO3 (0,1 mol L-1), pH 8. A mesma foi utilizada no preparo da solução de azul de metileno (MB) (0,25 x 10-3 mol L-1), no pré-tratamento do eletrodo de carbono vítreo (GC) por voltametria cíclica (CV) e no preparo de soluções para os estudos iniciais com o GCE-PMB. O pré-tratamento da superfície do eletrodo de GC foi realizado aplicando + 0,9 V por 240 s seguido de várias varreduras cíclicas de -0,4 a +1,0 V com velocidade de varredura de 50 mV s-1 até obter um perfil estável do voltamograma do eletrodo. Após o preparo do GCE-PMB, a atividade eletrocatalítica do eletrodo foi investigada para o Ácido Ascórbico (AA) e a L-Cisteína (L-Cys) por CV de -0,4 a +0,6. Foi observado aumento da corrente de pico e diminuição do sobrepotencial em relação ao eletrodo de GC. Nos estudos na presença do glifosato, o GCE-PMB apresentou resposta eletroquímica direta, por voltametria cíclica, para o glifosato (1,0 x 10-3 mol L-1) em solução de KCl 0,1 mol L-1 (pH 5,3) de -0,4 a +0,6 V e velocidade de varredura 50 mV s-1. A resposta voltamétrica apresentou picos anódico e catódico em 0,2 e 0, respectivamente. Para os estudos realizados por meio da técnica de voltametria de onda quadrada (SWV), os parâmetros freqüência, amplitude e incremento de varredura foram otimizados. A partir desses estudos foi possível obter informações relevantes sobre a interação do GCE-PMB com o glifosato. Os resultados mostraram que é possível observar a eletroatividade do herbicida glifosato sobre uma superfície eletródica sem a presença de metais como agentes complexantes. / This work describes the preparation, characterization and the use of the modified electrode with methylene blue polymer (PMB) immobilized onto the surface of glassy carbon electrode (GCE-PMB) in the analysis of the herbicide glyphosate. Concerning the methodology aspects, the method used for the preparation of the films PMB was the electropolymerization. The films prepared by this method present a differentiated characteristic such as robustness, stability and good redox properties. The optimized experimental conditions are the scan rate (50 mV s-1), the potential range (-0.4 to +1.2 V), the number of cycles (30) and the pH of the supporting electrolyte (pH 8). The supporting electrolyte solution was prepared from phosphate buffer solutions (0.05 mol L-1) and NaNO3 (0.1 mol L-1), pH 8. The same solution was used to prepare the solution of methylene blue (MB) (0.25 x 10-3 mol L-1), the pretreatment of the GC electrode by cyclic voltammetry (CV). It was also utilized in preparing solutions for the initial studies with GCE-PMB. The pre-treatment of the electrode surface of GC was performed, considering 0.9 V during 240 s, followed by several cyclic scans from -0.4 to 1.0 V (with scan rate of 50 mV s-1) until a stable profile of the voltammogram. After preparing the GCE-PMB, electrocatalytic activity it was investigated for Ascorbic Acid (AA) and L-Cysteine (L-Cys) by CV from -0.4 to +0.6 V. It was observed increase in peak current and decrease the overpotential comparing to glassy carbon electrodes. The GCE-PMB presented direct electrochemical response, for glyphosate (1 x 10-3 mol L-1) in KCl 0.1 mol L-1 (pH 5.3) from -0.4 to +0.6 V and scan rate 50 mV s-1. The voltammetric response showed anodic and cathodic peaks in 0.2 and 0, respectively. Using the square wave voltammetry (SWV), the parameters frequency, amplitude and scan increment were optimized. It was possible to find relevant information about the interaction between GCE-PMB and glyphosate. These results showed that is possible observe the electroactivity of glyphosate on a modified electrodic surface in absence of metals or complexing agents.

Orientadores: Alba Regina Monteiro Souza Brito, Anderson Luiz Ferreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T14:15:42Z (GMT). No. of bitstreams: 1 Manzo_LuisPauloBognoni_M.pdf: 4711838 bytes, checksum: 0267d7f30b132c874529cd6a03786252 (MD5) Previous issue date: 2012 / Resumo: A retocolite Ulcerativa Inespecífica e a Doença de Chron são as principais doenças inflamatórias intestinais. Apesar dos crescentes esforços, não se sabe ainda suas causas. Os tratamentos ainda não são eficazes, as drogas atuais são eficazes na indução da remissão mas não determinam sua cura. Os efeitos colaterais são severos, o que acarreta em baixa adesão ao tratamento. Os produtos naturais tem sido fonte de compostos usados por todo o mundo em diferentes áreas da medicina e ciência. O tratamento oral com geléia real na dose de 100 mg/Kg mostrou-se capaz de aumentar os níveis de grupamentos sulfídrica (GSH) e também a atividade da enzima glutationa peroxidase (GSH-Px) em camundongos com colite induzida por TNBS. A expressão de COX-2 e NF-kB também foram diminuídos, tais resultados demonstram efeitos antioxidantes e antiinflamatórios da geléia real nesta dose neste modelo de colite experimental. O Tratamento intrarretal com a proteína MRJP3 (50 ?g/animal) foi capaz de diminuir os níveis de IL-1? no cólon dos camundongos Balb/c submetidos a colite induzida por DSS. Uma vez que os níveis de IL-6 e IL-10 não foram alterados pelo tratamento intrarretal com MRJP3 50 ?g/animal, podemos afirmar que a proteína não atua pela via da IL-10. Estes efeitos antioxidantes e anti-inflamatórios observados durante o desenvolvimento da colite induzida por TNBS e por DSS em camundongos, podem ser de significativa importância pois abrem portas e encorajam novas pesquisas com a geléia real e sua respectiva proteína MRJP3, motivando novos estudos acerca de outos agentes antioxidantes e outros mediadores anti-inflamatórios envolvidos nestes modelos de colite experimental / Abstract: Ulcerative Colitis and Chron's Disease are the two major forms of IBD. Despite all efforts, these complications of the GTI are still lacking an effective therapy for their cure. Side effects, high cost and low adhesion to treatment are among the negative aspects. Natural products have been a source of widely used compounds in distinct areas of medicine and research. Royal Jelly (RJ) 100 mg/Kg was capable of augmenting the levels of glutathione (GSH) and the activity of glutathione peroxidase (GSH-Px) in mice undergoing TNBS-induced colitis. Furthermore, COX-2 and NF-kB had their expression decreased by the oral administration of RJ 100 mg/Kg. Intra-rectal MRJP3 treatment (50 ?g/animal) was capable of decreasing the levels of IL-1? in mice undergoing DSS-induced colitis, whereas the levels of IL-10 and IL-6 were not altered by MRJP3 50 ?g instillation, what indicates that this decrease is not IL-10-induced. The antioxidant and anti-inflammatory effects observed during the development of DSS and TNBS-induced colitis in mice, may be of crucial importance, since they open and encourage new studies focused on this nourishing substance, especially in experimental models of colitis / Mestrado / Farmacologia / Mestre em Farmacologia

The unwanted occurrence of biofilms in various industries requires critical remedial action in order to prevent their detrimental effects which potentially result in huge economic losses. Adequate monitoring of biofilms is a powerful tool to aid their thorough understanding and ultimate control. The Rotoscope is an instrument based on the principle of light absorption and reflection that was used in this study to monitor and study biofilms. Biofilm development of cocci and bacilli species was monitored using the Rotoscope and microscopy. Light reflectance decreased over time as the biofilm developed. Information on the different stages of biofilm development could also be deduced from light reflectance assays of the Rotoscope. Microscopy validated results which were obtained from light reflectance assays. Information on the morphology of the bacteria, depth of the biofilm as well as the different stages of biofilm development was deduced from EM and CLSM images. The Rotoscope was an easy, effective, on-line monitoring device for the development of biofilms. It was a lso showed to be useful in coll ecting informati on to help characterize bacteria species present within a biofilm The Rotoscope was integrated into a simulated soft drink (SO) production line to monitor biofouling and the efficacy of a clean-in-place (CIP) regime using electrochemically acti vated (ECA) water. During CIF the Catholyte and Anolyte (components of ECA) were effective as detergent and disinfectant respecti vely. This was indi cated by results obtained from microbial analysis of removable slides from the MPD, microscopic analysis, as well as pH, ORP and EC analysis. The absence of microbial growth and soil on microscope slides from the Rotoscope were a good indication of the high efficacy of Catholyte and Anolyte (components of ECA) as detergent and disinfectant respectively in a crp system. In addition, the re latively constant values reported for pH, ORP and EC before and aft er CIP suggests that the Catholyte and Anolyte were effective during CIF. The effect of Anolyte on trihalomethane (THM) formation was observed because of the presence of chl orine compounds. Low levels of THMs were obtained from CIP effluent which provided a good indicati on that Anolyte is an environmentally friendly alternative disinfectant compared to conventional disinfectants currently used in CIP. Increased pH and the presence of bromide resulted in an overall increase of THMs in systems using dissolved organic carbon (DOC) models (Glucose, maltose and phenol). There was however variation in the amount of THM produced using the three DOC models. The differences were attributed to the composition of organic matter in particular the aromacity and the nature and position of the functional groups of the model DOCs. / Dissertation (MSc)--University of Pretoria, 2012. / Microbiology and Plant Pathology / unrestricted

Orientador: Claudio Francisco Tormena / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T08:19:39Z (GMT). No. of bitstreams: 1 Sousa_RaphaelBellisde_M.pdf: 14524132 bytes, checksum: bd1305cbf90d194fc8c10bc82ddba77a (MD5) Previous issue date: 2012 / Resumo: Sabe-se que em sistemas do tipo A-CH2-B, onde A é um átomo (halogênio) ou grupo de átomos simétrico (CH3) e B é um grupo em que há ausência de simetria, os hidrogênios metilênicos (CH2), na maioria dos casos apresentam não-equivalência química, que significa dizer que os hidrogênios apresentam diferentes deslocamentos químicos. Dentre os inúmeros fatores que são considerados na interpretação de um espectro de RMN de H, a equivalência ou não-equivalência química dos hidrogênios metilênicos dos haloacetatos de 1-feniletila e de 2-fenilpropila está sendo abordada. Os sinais dos átomos de hidrogênios do grupo CH2X apresentaram um sistema de spin de segunda ordem AB para os compostos estudados, com exceção do iodoacetato de 2-fenilpropila, que tiveram deslocamentos químicos idênticos em solventes polares e apolares, como um sistema de spin A2. Cálculos teóricos de otimização estrutural possibilitaram encontrar as estruturas conformacionais mais estáveis para cada um dos compostos em estudo considerando o efeito do substituinte e do solvente, bem como avaliar quais fatores são responsáveis pelo comportamento observado. A espectroscopia no infravermelho foi fundamental para determinar o número de conformações presentes em solução. Para avaliar o efeito da distância entre o grupo CH2X e o centro assimétrico, foi estudado o cloroacetato de 3-fenilbutila. No caso do cloroacetato de sec-butila foi avaliado o efeito do grupo fenila sobre a não-equivalência química observada do grupo CH2X. Os resultados mostram que a não-equivalência química para hidrogênios metilênicos do grupo CH2X não dependem da distância entre esse grupo e o centro assimétrico, mas sim da conformação adotada pelo heteroátomo em relação ao grupo carbonila. / Abstract: It is known that in systems of the type A-CH2-B, where X is an atom (halogen) or group of atoms symmetrical (CH3) and Y is a group which has no symmetry plane, the methylene hydrogens (CH2), are in the most cases chemically nonequivalent, which means that the hydrogens present different chemical shifts. Among the many factors that are considered when interpreting a H NMR spectrum, the chemical equivalence or nonequivalence for the methylene hydrogens of the haloacetates of 1-phenylethyl and 2-fenilpropila is being broached. Signals pattern from hydrogen atoms in the CH2X group presented a second order AB spin system for studied compounds, with the exception of 2-phenylpropyl iodoacetate, which has identical chemical shifts in polar and apolar solvents, such as a A2 spin system. Theoretical calculations were performed to find out the most stable conformations for studied compounds in isolated phase as well as considering solvent effect. It was also theoretically evaluated, from NBO analysis, the most important interactions responsible for conformational preferences. Infrared spectroscopy was used to evaluate the number of conformations present in solution. The influence of the distance between CH2X fragment and asymmetric center was evaluated using phenylbutyl 3-chloroacetate as model compound and it was observed that even separated by five bonds the chemical non-equivalence of the methylene hydrogens persists in acyclic chains. The analysis of sec-butyl chloroacetate was important to judge whether the presence of the phenyl group in the molecule is required for chemical nonequivalence observed for the CH2X group. / Mestrado / Quimica Organica / Mestre em Química