A mediação do professor na constituição da autoria em textos de alunos de Letras

Textual composition in classroom has been object of research in language studies along this last three decades in Brazil. This thematic recurrence occurs is a demonstration of the gap between writing skill teaching and learner‟s performance. In this research, we argue that during writing process in classroom, teachers‟ mediated actions guide students to the exotopic exercise on their texts, facing it as a fundamental phase of their composition, with meaningful effect for the development of textual authorship. In this sense, we have chosen as investigation focus the textual composition of Letters Students at Universidade do Estado do Rio Grande do Norte – UERN - to study writing processual characteristics, based on teacher‟s mediation. The main aim of this research is to analyze students‟ (re)writing along Letters Course, to comprehend the process of authorship construction in their texts and the effects resulted through teacher mediation in this process. More specifically, a) to analyze teacher mediation as a mechanism for authorship development in texts composed by Letters Students; b) to deduce, based on different versions of textual composition, the effects of teacher mediation on students‟ writing; and c) to describe compositional textual process in classroom, identifying students‟ attitudes/behaviors before writing task. We have brought several voices into the dialogue, among them we highlight those based on bakhtinian studies. Some of those authors are related to Bakhtin circle, by themselves (BAKHTIN/VOLOCHINOV, [1929] 2006; BAKHTIN, [1979] 2003; [1963] 2008; [1975] 2010a; [1986] 2010b), their debaters (FARACO, 2008, 2009a, 2009b, 2010; PONZIO, 2010, 2012; GERALDI, 2010a; 2010b OLIVEIRA, 2006, 2008a, 2008b, 2010, among others), to guide us, mainly, on dialogism, author and authorship, and their conceptual implications: exotopy, finishing, esthetic activity, and ethical act. Data was constituted in teaching situation, involving teacher/researcher and 5th Term Letters/UERN students. Therefore, we have submitted an open questionnaire, textual discussion, and an article (re)writing. Data analysis has revealed subjects‟ little experience with writing composition in the Course, as a systematic practice, in their routine, dialogued, whose social function is explored. The texts are generally written in a single version and useful only to receive a score. Data analysis show insecure students in relation the writing, and with many difficulties to do it. On the other hand, writing movements, on the analyzed articles, have revealed that the subjects show a responsive attitude in relation to the mediated activities, to respond rewriting proposal. Despite some problems remain unsolved and many others emerge in each version of the article, in general, we consider that teacher mediation had a positive effect on student writing, considering that it boosted the author exotopic movement, something indispensable to compose a text. The three interventions carried out, in some way, provided opportunity for the subjects to modify their article.

Vicilina de sementes da leguminosa selvagem Anadenanthera macrocarpa: purificação, caracterização, efeito deletério e mecanismo de ação para Callosobruchus maculatus

Grains and legume seeds are foods that form the basis of the diets of many cultures around the world, winch contritbute to the daily nutrient requirements of humans. Vicilins (7S globulin) are storage proteins found in legume seeds, and may have an additional function constitutive defense of the embryo against pests and pathogens. In this work the vicilin from Anadenanthera macrocarpa - AmV (red-angico), was purified and partially characterized, its effect on development and larval survival and adult emergence of Callosobruchus maculatus was evaluated by determination of LD50, WD50 and ED50 in system bioassay. Purification of vicilin was initiated by the chitin affinity chromatography and then gel filtration (Superdex 75 Tricorn 10x300 mm) FPLC system followed by reverse phase chromatography (C8 phenomenex) on HPLC system. Bioassays WD50 and LD50 for larvae were 0.32% and 0.33% (w:w) respectively, since the ED50 for adults was 0.096%. The probable mechanism of action was evaluated by testing digestibility of AmV in vitro, and observed for the involvement of two fragments vicilins immunoreactive against polyclonal Anti-vicilin from Erythrina velutina (Anti-EvV) about of 22 and 13 kDa chitin binding. The AmV in its native form has been recognized by the anti-EvV, indicating that there is a conserved region in the vicilin and is probably corresponding to the chitin binding domains. These results point to a new vicilin chitin binding that can subsequently be used as a possible biopesticide protein source, in order to control insect pest C. maculatus and confirm literature findings that demonstrate vicilin in the presence of different kinds of ligands to conserved regions chitin not yet characterized

Injeção de vapor e solvente como um método de recuperação avançada em reservatório avançada em reservatórios de óleo pesado

Currently a resource more and more used by the petroleum industry to increase the efficiency of steam flood mechanism is the addition of solvents. The process can be understood as a combination of a thermal method (steam injection) with a miscible method (solvent injection), promoting, thus, the reduction of interfacial tensions and oil viscosity. The use of solvent alone tends to be limited because of its high cost. When co-injected with steam, the vaporized solvent condenses in the cooler regions of the reservoir and mixes with the oil, creating a zone of low viscosity between the steam and the heavy oil. The mobility of the displaced fluid is then improved, resulting in an increase of oil recovery. To better understand this improved oil recovery method, a numerical study of the process was done contemplating the effects of some operational parameters (distance between wells, injection steam rate, kind of solvent and injected solvent volume)on the accumulated production of oil, recovery factor and oil-steam rate. Semisynthetic models were used in this study but reservoir data can be extrapolated for practical applications situations on Potiguar Basin. Simulations were performed in STARS (CMG, 2007.11). It was found that injected solvent volumes increased oil recovery and oil rates. Further the majority of the injected solvent was produced and can be recycled

Quantificação de Fases Cristalinas de Incrustações em Colunas de Produção de Petróleo pelo Método Rietveld

The scale is defined as chemical compounds from inorganic nature, initially soluble in salt solutions, which may precipitate accumulate in columns of production and surface equipment. This work aimd to quantify the crystalline phases of scale through the Rietveld method. The study was conducted in scale derived from columns production wells in development and recipients of pigs. After collecting samples of scale were performed the procedure for separations of inorganic and organic phase and preparation to be analyzed at the X-ray Laboratory. The XRD and XRF techniques were used to monitor whether identifying and quantifying crystalline phases present in the deposits. The SEM technique was used to visualize the morphology of the scales and assess their homogeneity after the milling process. XRD measurements were performed with and without milling and with or without the accessory spinner. For quantify crystalline phases the program DBWStools was used. The procedure for conducting the first refinement was instrumental in setting parameters, then the structural parameters of the phases in the sample and finally the parameters of the function profile used. In the diffraction patterns of samples of scale observed that the best measures were those that passed through the mill and used the accessory spinner. Through the results, it was noted that the quantitative analysis for samples of scale is feasible when need to monitor a particular crystalline phase in a well, pipeline or oil field. Routinely, the quantification of phases by the Rietveld method is hardwork because in many scale was very difficult to identify the crystalline phases present