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Processamento sol-gel de pós bioativos vítreos e cristalinos
(Universidade Federal de São Carlos, 2010-03-19) Siqueira, Renato Luiz; Zanotto, Edgar Dutra; https://lattes.cnpq.br/1055167132036400; https://lattes.cnpq.br/0273898472927352
In recent years, the sol-gel process has been increasingly used in the preparation of glasses and glass-ceramics with biomedical applications. Although the precursors used in this synthesis methodology are a very important parameter, few studies have investigated their influence on the synthesis of these materials. In the present work, vitreous and crystalline bioactive powders of the systems SiO2−CaO−P2O5 and SiO2−CaO−Na2O−P2O5 were synthesized by means of a sol-gel route using different phosphorus precursors. The compounds chosen were triethylphosphate (OP(OC2H5)3), phosphoric acid (H3PO4), phytic acid (C6H18O24P6), and a solution prepared by dissolving phosphorus oxide (P2O5) in ethanol. The resulting materials were characterized by differential scanning calorimetry and thermogravimetry (DSC / TG), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM / EDS), and by in vitro bioactivity study. The use of different precursors significantly affected the main steps of the synthesis, beginning with the gelation time. The most striking influence of these precursors in the synthesis process was observed during the thermal treatments between 700 and 1200 °C for the conversion of the gels into ceramic materials. In this case, the samples, especially those prepared using phosphoric acid, exhibited very different mineralisation behaviours, but all were proven to be bioactive with in vitro tests. The bioactivity of these materials was strongly influenced by the treatment temperature, and in the case of the crystalline materials, also by the phases present. In vitreous materials, the bioactivity decreased with the stabilisation temperature. In the crystalline materials, the in vitro bioactivity was favored by the presence of wollastonite (CaSiO3) and alpha-tricalcium phosphate (α-Ca3(PO4)2) for the system SiO2−CaO−P2O5, and by sodium calcium silicate Na2Ca2Si3O9 for the system SiO2−CaO−Na2O−P2O5.
Inovação nas condições de cultivo visando o melhoramento da produção de vacina contra erisipela suína
(Universidade Federal de São Carlos, 2010-03-19) Machado, Maria Manuela Pereira; Zangirolami, Teresa Cristina; https://lattes.cnpq.br/4546701843297248; https://lattes.cnpq.br/8003315191142884
Pork is one of the most widely eaten meats in the world and pig farming is an economic activity booming in Brazil and the world. Several efforts have been made to develop more effective vaccines for major diseases that are affecting livestock such as swine erysipelas, caused by the bacterium Erysipelothrix rhusiopathiae. The currently available vaccines for the prevention of erysipelas are produced with culture broth of this microorganism inactivated or attenuated. The main antigenic agent identified is an protein fraction of 64-69 kDa, present in cell wall of bacteria and the supernatant of the culture. Given the accumulated knowledge of the studies conducted by Silva (2007), this study aimed to: i) study the conditions employed in the preparation of cell suspension for freezing and formation of culture stocks in crytubes and the stage of their activation; ii) studying the growth of E. rhusiopathiae, the formation of lactic acid and expression of antigen in culture media containing carbon sources alternative to glucose and in culture media containing nitrogen sources of plant origin; iii) to study the behavior of the microorganism in the new culture medium, animal-free, in a bioreactor. The studies for the improvement of the medium formulation were carried out in flasks incubated at static condition or under agitation of 200 rpm. The temperature was set at 37°C and the initial pH at 8,0 in all experiments. The studies in bioreactor were made using a 4.0 L stirred-tank bioreactor, with an agitation frequency kept between 100 and 700 rpm and air flow rate of 1.0 L/min. Samples of cell extracts made with choline chloride were analyzed by electrophoresis under denaturating conditions (SDS-PAGE) to evaluate the antigen expression. Studies of activation of the criotubes containing frozen cell suspensions led to the standardization of this step, with high reproducibility, and reduced activation time by 50%. The studies were grew with different carbon sources, showing that E. rhusiopathiae is able to assimilate galactose, lactose, and glucose. However, there was no assimilation of glycerol. The replacement of proteose peptone, a nitrogen source animal widely used in the cultivation of E. rhusiopathiae to produce bacterins, by Soytone, a soy peptone, animal-free, was a promising alternative for the production of the inactivated vaccine, helping to increase the specific growth rate and substrate conversion of cells in relation to values obtained in conventional medium. In batch cultivation performed in a bioreactor with medium containing glucose and Soytone, it was reached a biomass concentration of 10 g / L at 5 hours of cultivation. For the conventional medium, containing proteose peptone, the maximum cell concentration reported for the test batch in a bioreactor was approximately 2 g / L, which was reached after 7 hours of culture. Note also that a higher level of expression of antigenic protein in relation to those observed with peptone of animal origin was achieved in cultures performed with medium containing soytone.This result shows that could be incorporate the best practices of manufacturing practices for pharmaceutical and veterinary products, subject to the productivity of the process and with significant cost reduction.
Proposta de teste específico para determinação do limiar anaeróbio, limiar de compensação respiratória e máxima fase estável do lactato sanguíneo em judocas
(Universidade Federal de São Carlos, 2010-03-19) Azevedo, Paulo Henrique Silva Marques de; Perez, Sergio Eduardo de Andrade; https://lattes.cnpq.br/9408953831211309; https://lattes.cnpq.br/6559911217770194
Consciência e liberdade em Sartre: por uma perspectiva ética
(Universidade Federal de São Carlos, 2010-03-19) Moura, Carlos Eduardo de; Monzani, Luiz Roberto; https://lattes.cnpq.br/2036732603638197; https://lattes.cnpq.br/9919710226746652
L'avènement morale de Sartre exposé à travers de l'affirmation de la liberté, la seule base et la source de toutes les valeurs. La Conscience se constitue, au coeur de l'histoire, comme conscience morale en devenant évaluation et réflexion sur les valeurs, appelant à un fondement et ce fodement est «la conscience pendant que liberté": la conscience est la source du valeur. L'oeuvre moral que Sartre avait promis à la fin de L'être et le néant il peut trouver son prolongement dans les Cahiers pour une Morale, ce qui permet d'esquisser les contours d'une morale authentique comme une question angoissante cloué dans le coeur des hommes plutôt que d'une série d'exigences purement abstraites. La question centrale des Cahiers est sur la place du valeur dans le domaine de la morale, comme Sartre mettais à la fin de L'être et le néant a partir de la notion de liberté qui a ensuite formulé: liberté et responsabilité placée dans une dimension l'éthique. Le monde étant composé dans une relation d'interdépendance, l'autodétermination, la collectivitté et l'Histoire est que fonderont cette liberté et cette responsabilité éthiquement. Le point de départ de la pensée de Sartre est la subjectivité, avec la figure d'un homme qui est transcendance et, par conséquent, fait partie de l'histoire et est toujours en relation avec d'autres consciences, de sorte que le moral et la historialización affirment la liberté. Parler de la coexistence est mettre en avant de l'être une moral du devoir-être qui suppose une détotalisation, une création morale qui ne pourra jamais être indépendant des circonstances historiques: le cogito et la liberté sont la source de toute valeur. La morale de l'action et de l'engagement est soutenue par une liberté qui n'est pas abstraite, mais seulement exercée sur une situation concrète, par un individu qui produise la "totalité" et par elle soit produit. Il n'y a pas a priori, il n'y a pas de vérité révélées et c'est ainsi que le coefficient d'adversité se présente pendant le procès, qui permet à l'homme d'examiner ses valeurs et de exercer l'acte créatif: l'homme se engage dans une monde résistant. Comme il n'est pas seul, la valeur, le devoir et l'obligation appairaissent au moyen de un jeu dialectique des consciences libres. Ceci est la conception sartrienne de la reconnaissance du groupement humain comme totalité détotalisée . Par conséquent, seulement est possible de comprendre la morale à approfondir dans les relations entre la morale et l'histoire. Le «système des fins» ne peut être défini que par un sujet qui se projette dans l'avenir, qui construit ses propres possibilités, en et par la réalité humaine concrète. La praxis, défini par la perspective Dialectique de la tension entre le «Universel-Singulier», est donné par un sujet qui reconnaît sa propre autonomie et d'autres, est la actualisation de sa liberté et de l'autre et ce par une conversion qui se fait dans une situation: une vraie moralité concrète sera possible seulement par une action systématique sur la situation pour la suppression de l'aliénation.