Fibre-reinforced polymer-matrix composite materials have highly attractive physical properties which justify the present rapid increase in applications within industry. However, composite materials suffer, like every structural material, from a failure to achieve their design properties. Therefore this research project has investigated the processing of resin used in composite materials. Initially the research programme has been concerned with the cure of epoxy resins (specifically Araldite MY750 epoxy resin system), the behaviour of the resin as it cures and how the extent of cure can affect the mechanical properties of components. Therefore, investigations have been carried out into how resin cure can be monitored by the NMR spectra and the relaxation time properties. There were four methods of analysing the data investigated, overall transverse relaxation time (T2) and free induction decay data (FID) data using the Oxford QP NMR analyser, transverse relaxation time data and spectral changes for the individual chemical environments using the Jeol EX270 NMR spectrometer, curemeter investigations using the vibrating needle curemeter (VNC) and finally Barcol hardness investigations during the later part of the cure cycle. Both the Jeol NMR spectrometer and the Oxford QP NMR analyser are designed for use primarily with liquid-state experimentation, however for the spectral, relaxation time, and FID investigations results were obtained far longer in the cure than expected. Also for the T2 investigations a transition period was noticed in the data obtained that corresponded to the gel of the resin as determined by known viscosity data for that resin mix at that cure temperature. The use of NMR as a curemeter technique was verified by repeating the analysis of the resin cure at 40, 60, 80 and 100°C. This data was then compared to known viscosity data and cure profiles obtained by the VNC curemeter and Barcol hardness readings on similar sized samples.

>Magister Scientiae - MSc / Protein-protein interaction networks provide a global picture of cellular function and biological processes. Some proteins act as hub proteins, highly connected to others, whereas some others have few interactions. The dysfunction of a single highly connected interactor can cause widespread disruption of cellular processors including diseases and cancer. Therefore, detailed study of the interactions made by cancer-related proteins will help explain their role in the interaction networks. The investigation of proteins by mass spectrometry (MS) has provided unique opportunities to gain insight into the dynamics of these proteins at the molecular level. MS uses mass analysis for protein characterization, and is currently the most comprehensive and versatile tool in proteomics. MS can provide confirmation of protein samples of interest, accurate molecular mass measurements of proteins, purity of protein samples, detection of posttranslational modifications, and more recently, interactions between two or more proteins. The conventional way of investigating the structure of proteins involves nuclear magnetic resonance (NMR) or X-ray crystallography. Compared to MS these methods are time consuming methods and, furthermore, require a considerable amount of protein. MS has proved to be useful in this regard as it provides insights into the structural arrangement of proteins, and/or their interacting partners, without the need for crystalliastion or the tedious process of backbone assignment before structural and functional annotations can be attributed to the protein of interest. However, in many cases, conventional methods are used parallel to MS to serve as validation of the MS data. The broad objective of this MSc study was to provide structural and functional insights into the function of Retinoblastoma Binding Protein-6 (RBBP6), using a MS approach. The aims were twofold: 1) to investigate metal ion binding by RING (Really Interesting New Gene) finger domains from RBBP6, and 2) to investigate the in vitro interaction between RBBP6 and Hsp 70(Heat Shock Protein 70), and between RBBP6 and Murine Double Minute-2 (Mdm2).

The current generation of Glass Ionomer Cements (GICs) have many advantageous properties over other dental restorative materials but lack the compressive strength of these other materials. The aim of this project is to increase the compressive strength of conventional Glass Poly-Vinyl-Phosphonate cement by inclusion of reactive sub-micron filler particles. The setting characteristics, chemical reactivity and cement strength have been found using oscillating rheology, infrared spectrometry, nuclear magnetic spectrometry, transmission electron microscopy, potentiometer analysis, laser diffractometry and mechanical analysis. The addition of sub-micron filler particles in direct weight by weight replacement of aluminosilicate glass of a control material has increased the ultimate compressive strength of the new cement from 206MPa (control) to 250MPa after 365 days of aging. The strength of the new filler enhanced cements were comparable with the control material after 3 hours. The setting chemistry of the filler enhanced cements follows the same order as the control cement but at a decelerated rate. Theoretical modelling found that a large volume of sub-micron filler could fit into interstitial spacing in formed cement however the alteration of the aluminosilicate glass to polyelectrolyte ratio has been found to drastically alter the cement setting time. The use of cubic and polyhedral shaped filler particles as supposed to spherical particles may increase the cement strength further as greater packing densities are achieved. The formulation of a Glass Ionomer Cement with increased compressive strength may find use as a posterior restorative or as a better material for restoration of lesions and cavity liners.

A influência da obesidade sobre o fígado e a função hepática é tema ainda pouco estudado e discutido, principalmente no Brasil. O crescente aumento da população obesa de maneira global alerta sobre esse grave problema, que hoje em dia, se torna de saúde pública. Amplia-se, cada vez mais, o número de pessoas e a faixa etária atingida. A doença hepática não alcoólica é uma condição clínico-patológica comum caracterizada por depósitos de lipídios em hepatócitos no parênquima hepático. Um espectro de danos ocorrem no parênquima, desde uma simples esteatose macrogoticular podendo evoluir para esteato-hepatite, fibrose e até cirrose. Os casos de esteatose hepática não alcoólica (EHNA) que progridem para cirrose tem sido reconhecidos como a maior causa de morbidade e mortalidade com potencial para progredir para falência hepática. Apesar de haver um aumento na prevalência da doença hepática não alcoólica, os critérios para seu diagnóstico continuam pobremente definidos. A utilização da espectroscopia de prótons na ressonância magnética auxilia na quantificação do conteúdo lipídico hepático e na musculatura da perna (tibial anterior e sóleo), embora venha sendo utilizada apenas em pesquisas. Tivemos como objetivos o estudo do metabolismo lipídico de humanos xii obesos por espectroscopia por ressonância magnética, correlacionando com dados laboratoriais e de biópsias hepáticas. Neste estudo observacional transversal e prospectivo realizado em obesos, que foram submetidos a cirurgia redutora gástrica pela técnica de Capella no Hospital Prof. Edmundo Vasconcelos em São Paulo, foram incluídos 27 pacientes analisados no pré e pós-operatório para descrição dos dados. Foi constatada uma razão masculino/feminino geral de 8 :19 e a faixa etária entre 24 e 55 anos. Os índices de massa corpórea (IMC) eram sempre superiores a 40 Kg/m² para inclusão cirúrgica. Os pacientes obesos que no pré-operatório apresentavam esteatose hepática observada na ressonância magnética e esteatose e/ou esteato-hepatite na biópsia hepática evoluíram com melhora ou resolução no pós-operatório. Em conclusão, em pacientes obesos o grau de esteatose hepática pode ser analisado qualitativa e quantitativamente através da ressonância magnética com espectroscopia assim como, o controle pós tratamento cirúrgico evitando-se a utilização de métodos invasivos, entre eles a biópsia hepática. / The obesity influence on the liver and the hepatic function are themes that are not so discussed or studied, especially in Brazil. The world-wide increasing number of obese people calls the attention to this serious problem, that nowadays, became a public health problem. The number of people and the age of the people who suffer from it is increasing each day more. The non-alcoholic hepatic disease is a common pathological clinic condition caractherized by lipid deposits in hemocytes in the hepatic parenchyma. There are some injuries in the parenchyma, since a single steatosy macrogoticular to a steatohepatitis, a fibrosis and even a cirrhosis (Sass et al., 2005). The non-alcoholic steatosy hepatic (NASH) cases which lead to a cirrhosis have been known as the main causes of death with possibilities to evolute to a hepatic fail. Besides there is an increasing in the non-alcoholic hepatic disease, the means for its diagnosis still remain poorly defined. The protons spectroscopy use, in the magnetic resonance, helps on the lipidic hepatic contents numbers, although it has been used only for researches. We had as a goal the lipid metabolism study of obese human beings, related to the laboratorials data and the hepatic biopsy. On this study, where we observed obese people that were submitted to a gastric reducing surgery by the Capella techinic in the hospital Prof. Edmundo Vasconcelos in São Paulo, were included 27 pacients analyzed on the before and after operation for the datas description. It was noted a male/female general reason 9: 18 and the ages between 24 and 55 years old. The body mass indexes (IMC) were always over 40 Kg/m² to be included in a surgery. The obese patients who presented steatosy hepatic before operatory observed on the magnetic resonance and steatosy and/or steatohepatitis during the hepatic biosy went better on the pos-operatory. Finally, in obese patients the xiv steatosy hepatic degree can be analysed on its qualitativy and quantitativy through the magnetic resonance with spectroscopy, and so the cirurgical pos- treatment control, avoiding the use of invasive methods, among them the hepatic biopsy.

A influência da obesidade sobre o fígado e a função hepática é tema ainda pouco estudado e discutido, principalmente no Brasil. O crescente aumento da população obesa de maneira global alerta sobre esse grave problema, que hoje em dia, se torna de saúde pública. Amplia-se, cada vez mais, o número de pessoas e a faixa etária atingida. A doença hepática não alcoólica é uma condição clínico-patológica comum caracterizada por depósitos de lipídios em hepatócitos no parênquima hepático. Um espectro de danos ocorrem no parênquima, desde uma simples esteatose macrogoticular podendo evoluir para esteato-hepatite, fibrose e até cirrose. Os casos de esteatose hepática não alcoólica (EHNA) que progridem para cirrose tem sido reconhecidos como a maior causa de morbidade e mortalidade com potencial para progredir para falência hepática. Apesar de haver um aumento na prevalência da doença hepática não alcoólica, os critérios para seu diagnóstico continuam pobremente definidos. A utilização da espectroscopia de prótons na ressonância magnética auxilia na quantificação do conteúdo lipídico hepático e na musculatura da perna (tibial anterior e sóleo), embora venha sendo utilizada apenas em pesquisas. Tivemos como objetivos o estudo do metabolismo lipídico de humanos xii obesos por espectroscopia por ressonância magnética, correlacionando com dados laboratoriais e de biópsias hepáticas. Neste estudo observacional transversal e prospectivo realizado em obesos, que foram submetidos a cirurgia redutora gástrica pela técnica de Capella no Hospital Prof. Edmundo Vasconcelos em São Paulo, foram incluídos 27 pacientes analisados no pré e pós-operatório para descrição dos dados. Foi constatada uma razão masculino/feminino geral de 8 :19 e a faixa etária entre 24 e 55 anos. Os índices de massa corpórea (IMC) eram sempre superiores a 40 Kg/m² para inclusão cirúrgica. Os pacientes obesos que no pré-operatório apresentavam esteatose hepática observada na ressonância magnética e esteatose e/ou esteato-hepatite na biópsia hepática evoluíram com melhora ou resolução no pós-operatório. Em conclusão, em pacientes obesos o grau de esteatose hepática pode ser analisado qualitativa e quantitativamente através da ressonância magnética com espectroscopia assim como, o controle pós tratamento cirúrgico evitando-se a utilização de métodos invasivos, entre eles a biópsia hepática. / The obesity influence on the liver and the hepatic function are themes that are not so discussed or studied, especially in Brazil. The world-wide increasing number of obese people calls the attention to this serious problem, that nowadays, became a public health problem. The number of people and the age of the people who suffer from it is increasing each day more. The non-alcoholic hepatic disease is a common pathological clinic condition caractherized by lipid deposits in hemocytes in the hepatic parenchyma. There are some injuries in the parenchyma, since a single steatosy macrogoticular to a steatohepatitis, a fibrosis and even a cirrhosis (Sass et al., 2005). The non-alcoholic steatosy hepatic (NASH) cases which lead to a cirrhosis have been known as the main causes of death with possibilities to evolute to a hepatic fail. Besides there is an increasing in the non-alcoholic hepatic disease, the means for its diagnosis still remain poorly defined. The protons spectroscopy use, in the magnetic resonance, helps on the lipidic hepatic contents numbers, although it has been used only for researches. We had as a goal the lipid metabolism study of obese human beings, related to the laboratorials data and the hepatic biopsy. On this study, where we observed obese people that were submitted to a gastric reducing surgery by the Capella techinic in the hospital Prof. Edmundo Vasconcelos in São Paulo, were included 27 pacients analyzed on the before and after operation for the datas description. It was noted a male/female general reason 9: 18 and the ages between 24 and 55 years old. The body mass indexes (IMC) were always over 40 Kg/m² to be included in a surgery. The obese patients who presented steatosy hepatic before operatory observed on the magnetic resonance and steatosy and/or steatohepatitis during the hepatic biosy went better on the pos-operatory. Finally, in obese patients the xiv steatosy hepatic degree can be analysed on its qualitativy and quantitativy through the magnetic resonance with spectroscopy, and so the cirurgical pos- treatment control, avoiding the use of invasive methods, among them the hepatic biopsy.

Les verres de phosphates de zinc et gallium contenant de l’argent ont permis des développements originauxau travers de la structuration d’architectures photoniques multi-échelles innovantes en volume, en surfaceou sur fibre, et également à travers l’ingénierie de composition chimique du matériau. Un taux accru d’oxyded’argent permet de maximiser la quantité de paires au sein de la matrice vitreuse lors de la synthèse dumatériau. Ce dimère favorise les processus d’agrégation conduisant à la formation d’espèces lors del’interaction locale entre le verre et le laser femtoseconde infrarouge. Une étude par spectroscopie RPEmenée sur des échantillons irradiés par des sources ionisantes a permis de montrer que le débit de dose estprépondérant quant au contrôle des processus chimiques. Des centres à électron et à trou sont les espècesmajoritairement stabilisées à faible débit de dose, alors que la formation d’agrégats d’argent luminescentsintervient pour des puissances crête élevées typiques des lasers ultra-courts. Le caractère local de lastructuration par Direct Laser Writing a permis de créer des objets 3D originaux. L’analyse fine de ladistribution chimique au sein d’objets fluorescents a permis de montrer clairement une zone de déplétion enions argent au centre. Les effets de migration d’ions depuis le centre du faisceau laser vers le bord externea ainsi été mis en évidence. Le dopage des verres photosensibles par des ions europium a permis de montrerdes effets de synergie entre agrégats d’argent photo-inscrits et lanthanides trivalent. En effet, une exaltationde l’émission de luminescence de ces derniers à l’endroit des structurations laser a été mesurée. / The silver-containing phosphate glasses allowed original developments throughout the microstructuring ofarchitectures for innovative photonic in the volume, at the surface or in the fibered material. The chemicalengineering of the material plays an important role from this point of view. An increasing silver oxide ratioleads to an important quantity of pairs in the pristine glass matrix. This dimer in favor of the aggregationprocess bringing to the production of species during the interaction between the glass and the infraredfemtosecond laser. A study conducted by EPR spectroscopy on irradiated samples (ionizing sources)demonstrated that the dose rate is predominant for the control of the involved chemical process. Mainly,electron and holes are stabilized at low dose rate whereas the formation of luminescent silver clusters occursfor high peak power typical of ultra-short lasers. The Direct Laser Writing process allows local structuring ofthe matter and resulted in original tridimensional patterns. The fine chemical distribution analysis insideannular fluorescent objects clearly showed a depletion zone of the silver concentration in the center. Ionicmigration effects from the center towards the edges of the laser beam are then highlighted. The Eu3+-dopedphotosensitive glasses emphasized a synergy between photo-induced silver clusters and trivalentlanthanides. Indeed, a luminescence exaltation associated to the europium emission is measured.