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Item Interações da albumina de soro bovino com surfactantes e efeitos de antioxidantes sobre a oxidação de lipoproteínas de baixa densidade induzida por íons de cobre(Universidade Federal de Goiás, 2012-08-02) ANJOS, Jorge Luiz Vieira dos; ALONSO, Antônio; http://lattes.cnpq.br/5013069863616789Human plasma contains primarily large proteins, ranging in composition and concentration as the individual's physiological state. Among these proteins, albumin and low density lipoprotein (LDL) have been widely studied. The albumin (the most abundant protein in blood plasma) is responsible for important functions in the human body due to its excellent ability to bind and transport small molecules. In turn, the LDL (responsible for transporting cholesterol to the cells) in its oxidized form is directly associated with atherosclerosis, the main cause of cardiovascular disease. In the first part of this work, the interaction of bovine serum albumin (BSA) with the ionic surfactants sodium dodecylsulfate (SDS), cetyltrimethylammonium chloride (CTAC) and N-hexadecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (HPS) was studied by electron paramagnetic resonance (EPR) spectroscopy of spin label covalently bound to the single free thiol group of the protein. In the second part was studied the oxidation of human LDL by copper ions and also the antioxidant potential of polyphenols resveratrol, (+)-catechin and quercetin, using the EPR of a spin label, derived from stearic acid (5-DSA), and the method malondialdehyde content (MDA). Part I: The dynamics of the BSA and the thermodynamic parameters for transferring the nitroxide side chain from the more motionally restricted to the less restricted component were monitored through EPR spectra simulation. Whereas SDS and CTAC showed similar increases in the dynamics of the protein backbone for all concentrations used, HPS presented a smaller effect at concentrations above 1.5mM. At 10mM of surfactants and 0.15 mM BSA, the standard Gibbs free energy change was consistent with protein backbone conformations more expanded and exposed to the solvent, but with a less pronounced effect for HPS. In the presence of the surfactants, the enthalpy change, related to the energy required to dissociate the nitroxide side chain from the protein, was greater, suggesting a lower water activity. The nitroxide side chain also detected a higher viscosity environment in the vicinity of the Mal-5 induced by the addition of the surfactants. The results suggest that the surfactant-BSA interaction, at higher surfactant concentration, is affected by the affinities of the surfactant to its own micelles and micelle-like aggregates. Complementary DLS (Dynamic Light Scattering) data suggests that the temperature induced changes monitored by the Mal-5 reflects local changes in the vicinity of Cys-34 BSA residue. Part II: The oxidative process induced by copper ions results in lipid peroxidation of LDL (evidenced by high concentration of MDA) could also be monitored by the decrease in the dynamics of 5-DSA, reflected in increased spectral parameter 2A//. The oxidation of LDL resulted in increased energy barrier that the spin labels must overcome to achieve higher degrees of motion. All polyphenols studied were able to protect LDL completely against oxidation for concentrations from 30 M, whereas the protection provided by the Butylated hydroxytoluene (BHT) occurred only partially. This result, based on data from the literature, was attributed to the ability of polyphenols act as scavenger and chelating agents, while the BHT acts just like scavenger due the presence of only a single hydroxyl group in its molecule.Item Formação do professor e docência em Química em rede social: estudos sobre inclusão escolar e o pensar comunicativo(Universidade Federal de Goiás, 2011-12-05) BENITE, Claudio Roberto Machado; BENITE, Anna Maria Canavarro; http://lattes.cnpq.br/8433607360245647This study investigated the use of collaborative social network as a training environment for critical reflection. The research intends to contribute to the understanding of the use of research networks as spaces to provide critical reflection, the understanding of the use of research networks as spaces to develop interventions in educational action and the study of training teachers of science/chemistry focusing school inclusion. The theoretical foundation of the study is centered on the Theory of Communicative Action by Habermas, suitable for analyzing the movement of action and on Vigotski the reference needed to reflect the production of speech. Participated in this study the components of the Rede Goiana Interdisciplinar de Pesquisa em Educação Especial/Inclusiva RPEI , five trainer teachers, eight graduate students, thirteen undergraduate students and twelve teachers of basic education, besides students of the licentiate course in chemistry from four higher education institutions, all from Goiás State. Reflecting about the relationship between research and teaching activities, this research was configured as an action-research, divided into three spiral cycles: the first featured by discussions on face-to-face environment in RPEI, involving theoretical and practical conceptions about the training of teachers for inclusion; the second, by the identification of conceptions of trainer teachers of chemistry from a higher education institution about school inclusion and teaching activities in this perspective; finally the third spiral cycle represented the plan of action through discussion forums in virtual environment, contribution to the formation of chemistry teachers on inclusion. Analyzing the dialogical activities on Moodle platform, our results pointed out that the activities like this allow us understanding how the language that express the verbal thought is employed by those involved in a dialogue. Also it has permitted to identify the processes that the participants use to appropriate social languages relative to pedagogical actions to chemistry teaching, in an inclusion perspective when mediated by experienced teachers, aiming the mutual understanding among those involved.Item Desenvolvimento do Software PlanEx de planejamento de experimentos online e sua aplicação didática na pós-Graduação(Universidade Federal de Goiás, 2012-04-02) BÔSSO, Antônio Rafael de Souza Alves; SOARES, Marlón Herbert Flora Barbosa; http://lattes.cnpq.br/9698540158266610; OLIVEIRA, Anselmo Elcana de; http://lattes.cnpq.br/0369339073291948This work describes the design of experiments and response surface methodology (RSM) via factorial designs programmed in PlanEx, a new web/online software implemented using the Java language. The goal was to develop and validate PlanEx as a simple, efficient, and an interactive tool for undergraduate teaching and research. PlanEx was also designed as a free software, and the Java language was chosen since it is a community-developed open source software. PlanEx provides both full factorial design of experiments (2k) and fractional (2k-1), with up to six variables, and with, or without, replicates. PlanEx was also developed to perform variable screening through replicates, and normal probability plots and also to evaluate the model bias by the residual graphs. PlanEx is based on RSM with up to four variables at three levels, and central points with, or without, replicates. Through RSM the user can check linear or quadratic models to predict experimental responses through 3D surface plots, and analysis of variance (ANOVA). PlanEx was also evaluated in the second term of 2009, 2010, and 2011 in graduate courses of planning and design of experiments. The results have shown that PlanEx is fast, and interactive, and it is a simple design of experiment tool for both teaching and research.Item Soluções localizadas em modelos de campos relativísticos e em condensados de Bose-Einstein(Universidade Federal de Goiás, 2010-07-09) CARDOSO, Wesley Bueno; AVELAR, Ardiley Torres; http://lattes.cnpq.br/5732286631137637This work combines some of the results obtained on the study of solitons in relativistic fields and Bose-Einstein condensates. By using a first order formalism to solve the equations of motion of relativistic fields, introduced previously by our group, we construct several classes of lump solutions described by a single real scalar field. We show how these solutions can be controlled depending on a single parameter in the field potential. In condensed matter the solutions of the lump type correspond to bright solitons, very studied in the context of nonlinear crystals, fiber optics, Bose-Einstein condensates, etc. In all these cases, such solutions are obtained via a nonlinear Schr¨odinger equation, responsible for describing the propagation of pulses in optical fibers or crystals, or the atomic density in condensates. In this sense, our main goal is to study the soliton and breather modulations via nonlinear Schrodinger equation. We concentrate on the Bose-Einstein condensate in which the modulation of atomic density can be accomplished through the Feshbach resonance. We study cases where the nonlinearity is described by terms cubic, cubic and quintic, and purely quintic in the nonlinear Schr¨odinger equation. Also, situations where two interacting condensates in which the nonlinear Schr¨odinger equations are coupled, breather modulations, and the study of the soliton behavior under influence of chaotic, random and non-periodic perturbations in the nonlinearity of the system. In many cases we consider the condensate trapped in the cigarshaped configuration, i.e., with freedom in only one spatial dimension. Numerical simulations are performed to verify the stability of the solutions.Item Variabilidade química dos óleos essenciais e do teor de fenóis em folhas e frutos da jabuticabeira (Myrciaria cauliflora)(Universidade Federal de Goiás, 2012-06-29) DUARTE, Alessandra Rodrigues; FERRI, Pedro Henrique; http://lattes.cnpq.br/2129799749473005Foliar contents of total phenols and tannins and the essential oil composition of Myrciaria cauliflora populations cultivated in six sampling sites have shown the presence of four clusters related to soil types and foliar nutrients. Cluster I included samples which originated from sandy soil (S1) with the highest and lowest percentages of γ-eudesmol (11.55%) and germacrene D (20.48%), respectively, as well as high total phenol (136.68 mg/g) and tannin (60.72 mg/g) contents. Cluster II, rich in elemol (4.61%), included all the samples cultivated from clay sand loam soils (S2, S3, and S6), whereas clay soils S4 (cluster III) and S5 (cluster IV) had the highest amounts of germacrene D (III: 27.20%; IV: 26.83%) and the lowest levels of elemol (2.12%; 2.55%), total phenols (79.69 and 111.77 mg/g), and tannins (34.04 and 44.51 mg/g). Canonical redundancy analysis (RDA) revealed the relationship between chemical balances in the soil and leaf nutrients in different clusters. Chemovariations may be environmentally determined. Additionally, essential oil chemical composition and phenolics (total phenols, tannins, anthocyanins), reducing sugar and fruit acidity contents of Myrciaria cauliflora were obtained from same cultivated populations. RDA and discriminant analyses revealed four clusters of samples based on contents of α-copaene, tannins, reducing sugar and fruit acidity as predictor variables. The total variation partition performed by partial RDAs showed a strong influence of edaphic factors on phenolics, reducing sugar and fruit acidity data set. However, the polymorphism of essential oils may be genetically determined. Spatial influence on chemovariations was significant for all constituents, but less pronounced for essential oil data.Item Do compromisso à responsabilidade lúdica: ludismo no ensino de Química na formação básica e profissionalizante(Universidade Federal de Goiás, 2011-06-14) FELÍCIO, Cínthia Maria; SOARES, Marlón Herbert Flora Barbosa; http://lattes.cnpq.br/9698540158266610This work can appears like a proposal for reflections in education by chemistry in basic training, the use of playful activities as teaching resource and student engagement in the chemistry study. It can to promote a development of the play culture in the school and from school. The teacher can propose partnership and involvement of students to develop of autonomy and self-knowledge through participation in education self process. It can be a good alternative to students and teachers, when they intentionally work together to build norms and rules that should govern their actions in playgames, or games that the students participate together for a invention of theirs freedom (legaliberté) of action in the classroom through the rules of law that guarantees and serve the educational process. The teacher provides fundamental knowledge relevant to the playfulness and search experience with theirs students and build a pact of playfulness. The playfulness lived in the classroom and in activities of daily life, we believe that this can server to produce of a playgames culture, which considers the playful freedom and this legality, as a means of working the autonomy, the moral and intellectual development of students through education in chemistry. The intensification of dialogical processes and increasing intersubjectivity are seen as a stimulus to the study and understanding of the phenomena being studied. Those processes are seen as a stimulus to the study and to understand the phenomena that we are studying. Chemistry students in the basic training or professional education were challenged to participate and be involved with enthusiasm, they can do more efforts to know the concepts and answer the correctly theirs questions that the teacher or a opposite team to win the play, so they study more and do their better. So the study seem more funny pleasure study and seeks to answer the questions presented in an interdisciplinary way. Leisure activity, in which case the picnic chemical, appears as a novelty in the classroom, a way for students to share their world with peers and teachers and learn more about the chemical composition of foods preferred by them. In response to our initial question, answered by students with suggestions and ideas, seems that they know how to enjoy learning. The teacher consideration of theirs will serve as a catalyst for change and improvement in the classroom participation and sharing of information more meaningful. It could transcend the school and may be evidence for a paradigm change in the educational development of chemical concepts at college. The use of computational resource it is a strategic so good to do sense at chemistry concepts. To work with attention on language and make the students to play with perception, about the different senses of words and learn more. The educator can make questions and to encourage the students that they can participate in drawing up rules and commitment to the good performance activities of their learning process. This is essential to increase the ludic culture and environmental awareness. To learn and understand the meaning of scientific language with gain of meaning in a play activity, we have proposed interdisciplinary partnerships, information technology resources and ludism. An education based in ludic principle can help to improve education in chemistry for the development of professional autonomy and citizenship.Item Desenvolvimento de método químico analítico forense para análise de merla por Análise Térmica e Cromatografia Gasosa de Alta Resolução(Universidade Federal de Goiás, 2011-03-18) MEDEIROS, Rodrigo Irani; LELES, Maria Inês Gonçalves; http://lattes.cnpq.br/1614912440064013An analytical chemical method for the forensic analysis of an illicit drug merla, whose the main constituent is the cocaine was development. Thermogravimetric analysis admitted to understand the thermal behavior of samples and quantifying the stages of mass loss, which together with the quantification endothermic event in DSC, the results were essential for the generation of analytical answers used to construct the data matrix of the statistical analysis. An efficient process for the precipitation of inorganic substances was established, which simultaneously allowed the extraction of two liquid fractions, organic and aqueous, being determinate a partition coefficient of 96,22 % for cocaine, using ethyl acetate as solvent, which showed lower elution time (0.58 min.) among the solvents evaluated. A method by Fast GC for cocaine analysis was developed, reducing the analysis time of 14.5 to 4.5 min was developed, which allowed analyze merla sample and the normalization of the chromatographic peaks of cocaine, demonstrated the great variation of its concentration in merla. Noticed of the potential of the method involving the thermo-analytical and chromatographys techniques to generate experimental results obtained statistically enabled a classification and grouping of samples by Euclidean Distance by the Hierarchical Cluster Analysis (HCA), estimated whether seized samples with different users were manipulated in the same laboratory and if determined city has separate laboratories for illegal preparatiom of drug narcotic.Item Atividades de experimentação investigativas lúdicas no ensino de química:(Universidade Federal de Goiás, 2009-12-11) OLIVEIRA, Noé de; SOARES, Marlón Herbert Flora Barbosa; http://lattes.cnpq.br/9698540158266610This Thesis presents a brief historic of experimentation, its application in secondary schools and the justification for the alternative material utilised during the activities of experimentation. Some playful conceptual aspects, its presentation and its application at school are also described with the aim of observing the existence of the relations between the playful and the activities of experimentation. Referring to the method, we have opted for the method study of multiple cases, aiming to conduct a comparison amongst several students and schools that utilise different experiments in an attempt to relate the similarities to the context of the research focus. The development in the application of the activities of experimentation is described in different groups from three secondary schools, two being in the city of Dourados-MS and one in the city of Goiânia- GO. This paper also presents an analysis of several articles related to experiments published by magazines such as Química Nova (New Chemistry) and Química Nova na Escola (New Chemistry at School), taking into consideration the following criteria: the availability of activities of experimentation for the teaching of chemistry, types of experimentation, laboratory material and reagents utilised, adequacy to the classroom, type of questionnaire, relationship with daily life, and the possibility of the presence of the playful if performed by the student. The Atividade de Experimentação Investigativa Lúdica AEIL (Activity of Investigative Playful Experimentation) is being proposed as another subsidy for the practice of experimental activities, with the possibility of being performed in the classroom