51 resultados para Gilberto Dupas


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In this dissertation, the theoretical principles governing the molecular modeling were applied for electronic characterization of oligopeptide α3 and its variants (5Q, 7Q)-α3, as well as in the quantum description of the interaction of the aminoglycoside hygromycin B and the 30S subunit of bacterial ribosome. In the first study, the linear and neutral dipeptides which make up the mentioned oligopeptides were modeled and then optimized for a structure of lower potential energy and appropriate dihedral angles. In this case, three subsequent geometric optimization processes, based on classical Newtonian theory, the semi-empirical and density functional theory (DFT), explore the energy landscape of each dipeptide during the search of ideal minimum energy structures. Finally, great conformers were described about its electrostatic potential, ionization energy (amino acids), and frontier molecular orbitals and hopping term. From the hopping terms described in this study, it was possible in subsequent studies to characterize the charge transport propertie of these peptides models. It envisioned a new biosensor technology capable of diagnosing amyloid diseases, related to an accumulation of misshapen proteins, based on the conductivity displayed by proteins of the patient. In a second step of this dissertation, a study carried out by quantum molecular modeling of the interaction energy of an antibiotic ribosomal aminoglicosídico on your receiver. It is known that the hygromycin B (hygB) is an aminoglycoside antibiotic that affects ribosomal translocation by direct interaction with the small subunit of the bacterial ribosome (30S), specifically with nucleotides in helix 44 of the 16S ribosomal RNA (16S rRNA). Due to strong electrostatic character of this connection, it was proposed an energetic investigation of the binding mechanism of this complex using different values of dielectric constants (ε = 0, 4, 10, 20 and 40), which have been widely used to study the electrostatic properties of biomolecules. For this, increasing radii centered on the hygB centroid were measured from the 30S-hygB crystal structure (1HNZ.pdb), and only the individual interaction energy of each enclosed nucleotide was determined for quantum calculations using molecular fractionation with conjugate caps (MFCC) strategy. It was noticed that the dielectric constants underestimated the energies of individual interactions, allowing the convergence state is achieved quickly. But only for ε = 40, the total binding energy of drug-receptor interaction is stabilized at r = 18A, which provided an appropriate binding pocket because it encompassed the main residues that interact more strongly with the hygB - C1403, C1404, G1405, A1493, G1494, U1495, U1498 and C1496. Thus, the dielectric constant ≈ 40 is ideal for the treatment of systems with many electrical charges. By comparing the individual binding energies of 16S rRNA nucleotides with the experimental tests that determine the minimum inhibitory concentration (MIC) of hygB, it is believed that those residues with high binding values generated bacterial resistance to the drug when mutated. With the same reasoning, since those with low interaction energy do not influence effectively the affinity of the hygB in its binding site, there is no loss of effectiveness if they were replaced.

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The genus Saccharum belongs to Poaceae family. Sugarcane has become important monocultures in Brazil due to their products: ethanol and sugar. The production may change between different regions from Brazil. This difference is related to soil, climatic conditions and temperature that promotes oxidative stress that may induce an early flowering. The aim of this work was to identify the effects of oxidative stress. In order to analyse this, sugarcane plants were submitted to oxidative stress using hydrogen peroxide. After this treatment, the oxidative stress were analyzed Then, the plant responses were analyzed under different approaches, using morphophysiological, biochemical and molecular tools. Thus, sugarcane plants were grown under controlled conditions and until two months they were subjected first to a hydroponics condition for 24 hours in order to acclimation. After this period, these plants were submitted to oxidative stresse using 0 mM, 10 mM, 20 mM and 30 mM hydrogen peroxide during 8 hours. The histomorphometric analysis allowed us to verify that both root and leaf tissues had a structural changes as it was observed by the increased in cell volume, lignin accumulation in cell walls. Besides, this observation suggested that there was a change in redox balance. Also, it was analyzed the activity of the SOD, CAT and APX enzymes. It was observed an increase in the SOD activity in roots and it was also observed a lipid peroxidation in leaves and roots. Then, in order to identify proteins that were differently expressed in this conditions it was used the proteomic tool either by bidimensional gel or by direct sequencing using the Q-TOF EZI. The results obtained with this approach identified more than 3.000 proteins with the score ranging from 100-5000 ions. Some of the proteins identified were: light Harvesting; oxygenevolving; Thioredoxin; Ftsh-like protein Pftf precusor; Luminal-binding protein; 2 cys peroxiredoxin e Lipoxygenase. All these proteins are involved in oxidative stress response, photsynthetic pathways, and some were classified hypothetical proteins and/or unknown (30% of total). Thus, our data allows us to propose that this treatment induced an oxidative stress and the plant in response changed its physiological process, it made changes in tissue, changed the redox response in order to survival to this new condition

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Bacterial cellulose (BC) has a wide range of potential applications, namely as temporary substitute skin in the treatment of skin wounds, such as burns, ulcers and grafts. Surface properties determine the functional response of cells, an important factor for the successful development of biomaterials. This work evaluates the influence of bacterial cellulose surface treatment by plasma (BCP) on the cellular behavior and its genotoxicity potential. The modified surface was produced by plasma discharge in N2 and O2 atmosphere, and the roughness produced by ion bombardment characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Cell adhesion, viability and proliferation on BCP were analysed using crystal violet staining and the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium (MTT) method. Genotoxicity was evaluated using the comet and cytokinesis block micronucleus assay. The results show that the plasma treatment changed surface roughness, producing an ideal cell attachment, evidenced by more elongated cell morphology and improved proliferation. The excellent biocompatibility of BCP was confirmed by genotoxicity tests, which showed no significant DNA damage. The BCP has therefore great potential as a new artificial implant

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This dissertation is a proposal for dialogue between Brazilian Social Thought, History of Portuguese America and the Analytical Psychology of C.G. Jung, highlighting the following archetypes: Anima, Animus, Shadow and Persona. Directing the study to the image of Indian women in this Brazilian interpretation of Casa-Grande & senzala by Gilberto Freyre, have largely centered on denial of the feminine image as a creative and positive in the minds of Brazilian culture, where a more specific analysis. We assume that your work has inspired several bridges over imaginary things in Brazil, including aspects relating to miscegenation, the study of foreign travelers, Jesuits and settlers / invaders of the sixteenth and seventeenth centuries the Portuguese disembarked in America and in this sense, the influence of his work as wasteful image through time and space of the Portuguese slave order. Above all, we intend to do a reading of Native women thought in his book

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This essay discusses the race issue, emphasizing the racial concept in Casa-Grande & Senzala. We discussed the Brazilian intellectual scene of the 1920s and 1930s, also the decadence of the analysis based on the variables of race, geographical environment and climate, emphasizing the ascent of new approaches, structured cultural diversity in the capitalist economy and exclusionary. We use the concept of racialism, understanding it as any narrative that classifies the types of people in a racial criterion

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Tropical environments often face strong seasonal variations in climate, such as alternate periods of dry and rain, that may often be important influence in the annual X the organisms lives. Here we assess how population dynamics of two butterfly species (Heliconius erato and Heliconius mepomene) respond to environmental and seasonal variations. A mark-release-recapture study carried out in an Atlantic forest reserve, 15 Km from Natal, Rio Grande do Norte, Brazil, for 3 years, during the dry and rainy season, with three visits weekly done. Information such as species, wing lenght, site of capture, pollen load and phenotype (number of spots) (in H. erato only) were noted for each capture. Seasonal variation exists in capture rates of the two species, with great capture rates during the rainy season. Despite finding differences in the mean density of individuals of the two species among the different collection areas, this difference was only significant between floodplain and central areas, and no influence of seasonality was observed in the mean density between the areas. Seasonality in wing size was only observed for H. erato, with larger wings during the rainy season. Females carried larger pollen loads than males both species, but species were similar. Only males differed seasonally, with larger pollen loads during the rainy season. The distribution of the number of wing spots did not vary between the dry and rainy seasons, and the number of spots in males and females was similar. Therefore, we conclude that there was a strong influence of seasonal variation in the population dynamic of the two Heliconius species, as well as in several aspects of their biology

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High levels of local, regional, and global extinctions has progressively simplified communities in terms of both species and ecosystem functioning. Theoretical models demonstrated that the degree of functional redundancy determines the rates of functional group loss in response to species extinctions. Here, we improve the theoretical predictions by incorporating in the model interactions between species and between functional groups. In this study, we tested the effect of different scenarios of interspecific interactions and effects between functional groups on the resistance to loss of community functional groups. Virtual communities have been built with different distribution patterns of species in functional groups, both with high and low evenness. A matrix A was created to represent the net effect of interspecific interactions among all species, representing nesting patterns, modularity, sensitive species, and dominant species. Moreover, a second matrix B was created to represent the interactions between functional groups, also exhibiting different patterns. The extinction probability of each species was calculated based on community species richness and by the intensity of the interspecific interactions that act upon it and group to which it belongs. In the model, successive extinctions decrease the community species richness, the degree of functional redundancy and, consequently, the number of functional groups that remain in the system. For each scenario of functional redundancy, A, and B, we ran 1000 simulations to generate an average functional extinction curve. Different model assumptions were able to generate remarkable variation on functional extinction curves. More extreme variations occurred when the matrix A and B caused a higher heterogeneity in the species extinction probability. Scenarios with sensitive species, positive or negative, showed a greater variation than the scenarios with dominant species. Nested interactions showed greater variation than scenarios where the interactions were in modules. Communities with maximal functional evenness can only be destabilized by the interactions between species and functional groups. In contrast, communities with low functional evenness can have its resistance either increased or decreased by the interactions. The concentration of positive interactions in low redundancy groups or negative interactions in high redundancy groups was able to decrease the functional extinction rates. In contrast, the concentration of negative interactions in low redundancy groups or positive interactions in high redundancy groups was able to increase the functional extinction rates. This model shows results that are relevant for species priorization in ecosystem conservation and restoration

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This research work worries in building the history of the natalense priest Miguel Joaquim of Almeida Castro, Miguelinho, I don't just eat one of the heroes and martyrs of the Revolution From Pernambuco of 1817, as bill the traditional history, but also the educated man, the intellectual and the admired teacher. The studied period understands the beginning of the century XIX, when priest Miguelinho comes back to Brazil, coming of Portugal, to assume teacher's occupation in the Seminar of Olinda, and it ends in the year of 1817, marked by the Revolution From Pernambuco, one of the most important movements in the fight for the liberation of Brazil of the Portuguese domain. Miguelinho, one of the leaders of the Revolution, that also reached the provinces of Paraíba and of Rio Grande do Norte, it was executed by the real troops. Like this, he tries to understand the Priest's conflicting relationship, while representative clergyman, of a Church that almost obtained a religious monopoly, and your ideals per centuries more gone back to a social and economical order of Illumines, that even certain point condemned the attitude of the own Church. The objective, then, is to understand through the path of priest's Miguelinho life, not only the intellectual, the teacher and the revolutionary, but the representation of your political and pedagogic-educational ideas in a die historical moment and the creation of the republican myth, looking for the plurality of an universe that seeks, per times, to flee of our theoretical context

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This work is an analysis about the teacher's formation starting from certain aspects of its culture. It is supposed that the teacher is constituted in an individual that acts starting from singular aspects, in an individual point of view, but at the same time it interacts with other individuals in an environment strongly marked by the culture. Those two dimensions are representatives of the socio-cultural characteristics and they can be seen in the perspective of the individual and collective identity. Based on those presuppositions we chose, as reference, four environment of formation: the family, the school, the work and the Movement of the Rural Workers Without-Soil/MST (MST: The without-soil-ones in Portuguese) observing as the teachers refers to those environment highlighting, mostly, the formative aspects stood out. The individuals researched are teachers involved in the education of settled communities, who are students of the Earth Pedagogy course of the Universidade Federal do Rio Grande do Norte/UFFRN. For our analyses, we used narrative texts, written by the teachers, as conclusion of the discipline History of the Brazilian Education in which they tell their life histories. The speeches show as the environments of reference influence in their world conceptions, attitudes and values that not just mix in an individual dimension, but also collective. The research make us reflect about the possibility to think on the educational action starting from that understanding of wide formation considering the present elements in the courses of teacher's life

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The present study comes from inquietudes of an investigative posture assumed by a Physical Education Graduation Professor, before her educative action with undergraduate teachers. The research was done with 16 (sixteen) Kindergarten and Elementary School teachers, who teach at public schools. The referred teachers are undergraduate students of the Graduating Normal Course at Superior Educational Institute President Kennedy, in Natal/RN. The analysis and discussion of the intertwining of knowledge, within the four Pillars of Education, at the Fountain of Knowledge , is a metaphor, especially created for this study, as for its epistemological and methodological structure, guiding all the investigative process. It provided to show up the repercussion of bathing and drinking these humanizing waters of a pedagogical practice that values the Being, aiming his self-transcendence. The conclusions obtained were the following: 1) The professor, while bathing himself in the Fountain of Life Knowledge, reflects his personal and professional life, recalling feelings and emotions that through time were forgotten, but as they were remembered and lived again, impulse people towards humanity. 2) While bathing himself at the Fountain of Life Knowledge, the professor realizes he is awoken to humane knowledge, caring about his practices, which he develops in the classroom. Practices he considers the learning of knowing, of doing, of living together, and of learning how to be, having and integrated form on the Being. 3) When the worries about the developing of the Being exist coming from the undergraduate teacher there is a practice the shows up the web of corporeity knowledge knowing how to play, how to create, how to feel, how to think, and how to humanize. 4) The presence of the professional of Physical Education, with knowledge and experience of the budgets of corporeity, is essential in the process of graduating the Kindergarten and first years of Elementary School undergraduate teacher, for he, the former, has a huge responsibility as to the learning and developing of the educational process the humanizing developing of the Being In a proposal of education that occurs through the whole life. 5) The Professional of Physical Education has positions to conquer, for the existent gap in the educational process, as for the understanding of the body and of corporeity in the perspective of totality, urges to be modified in name of another mankind, with full humanity

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Cet article propose, à partir d'une analyse de trois expériences différentes de la formation des enseignants, voir la pratique de l'enseignant comme une réalité et la comprendre, dans cette perspective, dynamique, génératrice de contenu et possible d être transformée. Une étude menée par un groupe de chercheurs de Sao Paulo do Potengi / RN avec des enseignants des écoles municipales dans les années 70, la mise en oeuvre du projet de réorientation curriculaire par le Bureau d Éducation de la ville de São Paulo - SP en 1989, et le cours Pédagogie de la Terre à l UFRN créée en 2002 sont pris en compte dans ce travail, comme des références dans la formation des enseignants qui démontrent à la fois les référentiel théorique et les actions développées sur la pertinence des réflexions par rapport à l'enseignement pratique comme point de départ quand on cherche à transformer l'école. Du matériel de lecture sur la manière dont ces processus de formation des événements a été possible de détecter la présence de deux éléments qui semblent être importants: la participation des personnes concernées et le reflet de leurs pratiques. Nous avons cherché à comprendre comment ces éléments apparaissent dans la pratique de deux étudiants du cours de Pédagogie de la Terre au cours de leurs classes de stage, en cherchant à identifier la façon dont ils font avancer ce point de vue de ce qui se passe dans le processus de formation. L'étude fait remarquer que la participation des sujets comme la réflexion collective des pratiques peuvent être cruciale pour la compréhension d'un enseignement qui peut être dynamique et de transformation des sujets, et qu elle peut se passer dans un processus de construction collective du savoir marquée par une refléxion et d une manière critique de faire et réflexive d'elle-même dans l'autonomie scolaire, améliorer la qualité de l'enseignement et le renforcement de l'enseignant et de l'élève comme des sujets actifs dans la reconstruction de leurs connaissances

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This Master of Science Thesis investigates in an exploratory modeling the idea of strategy consistency applying as an assessment tool a model of performance indicators of a higher education institution based on the balanced scorecard (BSC). It is carried on a review of conceptual BSC perspective hierarchy models and of studies on higher education institution in Brazil and worldwide. From a BSC model with three indicators at each perspective is carried on a case study with directors and coordinators of a private higher education institution with a descriptive and multivariate analysis using cluster analysis. The main findings point to a different perception of respondents on the importance level of the perspectives with a higher importance level given to Learning and Growth and Process that to Customer and Financial. Particularly, the financial perspective got a importance level significantly lower that the others, what suggests an inconsistency on the strategy deployment on the institution considered in terms of the perception of the managerial levels of the importance level of the perspectives

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The commitment assumed by Brazil to ILO in order to pursue actions toward the ILO/OSH-2001 adoption in the country poses the issue of modeling the institutional arrangement the set roles and relationship between government, standards organizations, health and safety organizations, professionals and other institutions to deploy the ILO/OSH-2001. This Thesis develop institutional arrangement models based on the current model and also in the ISO 9000 scheme and others. It is studied the US case with OSHA and VPP, the OHSAS 18001 and ANSI/AIHA Z-10, in addition to actual context of the regulating norms NR s. The scenarios developed are put to evaluation on feasibility, potential changes and effects on current MTE auditors work scheme. The main results are five scenarios developed and that the MTE auditors tend to be reactive to the change toward the ILO/OSH-2001.

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Particularly in Braziland in Rio Grande do Norte, companies manufacturing red ceramic, play an important role as agents of development to study the region Seridó- RN, specific place for carrying out the research. It is observed in this region a concentration of red ceramic industries of small size, which, despite its importance in the ceramic, they are unable to enjoy or use the new forms of administrative management and technological advances designed and offered by universities, centers of research and projects of governments, remained almost entirely outside the progress and modernization, technological and administrative. These companies still have outdated technology, and management processes, providing quality problems and standardization of end products. Upon these conditions are the companies going through crisis and struggling to survive alone and without assistance. The region of Seridó-RN, lets make a detailed case study of red ceramic companies in the region proposed from the existing theoretical and actual lifting of the condition of the product manufacturing red ceramic, allowing through this overview of the implementation of collect samples of raw materials, allowing the study of each ceramic industry that contributed to the participation of the research, which was determined parameters such as: analysis of the physical, chemical and technological properties of raw materials, characterization of the processes used, raising the technological resources considering equipment, machinery, supplies, raw materials and facilities available and its organization by type of products from companies involved in this study. The methodology consists of the following steps: collection of raw material, crushing and screening, characterization of raw materials (liquid limit, chemical analysis, mineralogical analysis, differential thermal analysis, sieve analysis), mixing, forming, cutting, drying and burning of ceramic bodies and bodies of evidence. The results showed that it was clay with distinct characteristics with respect to plasticity. With respect to the different compositions of mixtures of ceramic masses, we conclude that the ceramic properties showed a direct proportionality with increasing fraction of the clay not plastic. However, the compositions of the masses studied proved to be the most appropriate for the types of simulated clay for use in ceramics. Adopted in the ceramic processing made it possible to obtain products the resulted in consistent properties, and in some cases even exceeding the requirements of technical studies and standard-Brazilian clays to obtain ceramic products such as tiles, bricks and tiles to floor. Based on the discussions from the results obtained in the various processing steps of this work, one can draw conclusions according to the physico-chemical and mineralogical properties of raw materials, the properties of ceramic products burned and analysis. This work may be used by other researchers, private companies and governmental organizations, undergraduate students and graduate, can develop studies and future research to: develop projects to modify the furnaces; mapping projects develop and rationalize the exploitation of raw materials ;promoting reforestation and forest management; develop reduction projects and recovery of waste; develop training projects in manpower sector, and develop security projects, improving the conditions of work in the area pottery

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The accomplishment of this work was motivated by our concerns, while teacher of Physics discipline, in the medium teaching and in the higher education, where we have been observing a lot of difficulties in the students' acting, to the they try to give pursuit out to their studies of the classroom, because of the lack of appropriate equipments, or even, of a laboratory where they can put in practice the studied contents. The work aims at to build and to test an educational software that it serves as tool auxiliadora in Physics learning in the Medium Teaching, in the area of electricity, with emphasis in the study of the electrodynamic in resistors. The developed software comes as an alternative to the learning problems, putting the computer science as auxiliary tool, because, besides being an alternative in the middle of the technological expansion, endowed with several resources, it stimulates the significant learning, according to David Ausubel's perspective. A software containing a program destined to the applicability of physics contents in the branch of the electricity is presented as an auxiliary tool, where the student can, not just, to review the contents presented at room, as well as for in practice, through a virtual laboratory, some of these contents, besides testing their knowledge through a bank of discursive subjects. The evaluation of the developed software was made submitting him/it to the professionals' of physics area appreciation. Equally, through continuous evaluations, they were made comparisons among the students' of five different groups acting, in the same school, that you/they were used of the program as tool of his auxiliary learning, and the acting of those that didn't use it