Sistema microemulsionado: caracterização e aplicação na indústria de petróleo

Alkyl polyethoxylates are surfactants widely used in vastly different fields, from oil exploitation to pharmaceutical applications. One of the most interesting characteristics of these surfactants is their ability to form micellar systems with specific geometry, the so-called wormlike micelle. In this work, microemulsions with three distinct compositions (C/T = 40 %, 30 % and 25 %) was used with contain UNITOL / butanol / water / xylene, cosurfactant / surfactante (C/S) ratio equal to 0,5. The microemulsion was characterized by dynamic light scattering (DLS), capillary viscometry, torque rheometry and surface tensiometry experiments carried out with systems based on xylene, water, butanol (cosurfactant) and nonaethyleneglycolmonododecyl ether (surfactant), with fixed surfactant:cosurfactant:oil composition (with and without oil phase) and varying the overall concentration of the microemulsion. The results showed that a transition from wormlike micelles to nanodrops was characterized by maximum relative viscosity (depending on how relative viscosity was defined), which was connected to maximum effective diameter, determined by DLS. Surface tension suggested that adsorption at the air water interface had a Langmuir character and that the limiting value of the surfactant surface excess was independent of the presence of cosurfactant and xylene. The results of the solubilization of oil sludge and oil recovery with the microemulsion: C/S = 40%, 30% and 25% proved to be quite effective in solubilization of oil sludge, with the percentage of solubilization (%solubilization) as high as 92.37% and enhanced oil recovery rates up to 90.22% for the point with the highest concentration of active material (surfactant), that is, 40%.

Diferenças entre critérios normativos e autopercebidos na identificação da necessidade de tratamento ortodôntico, satisfação com a aparência e mastigação em adolescentes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Influência da técnica de fabricação e dos materiais sobre o ajuste da interface pilar/implante em infraestruturas implantossuportadas

The aim of this study was to compare the misfit vertical, horizontal and passivity of zirconia and cobalt-chromium frameworks fabricated for CAD / CAM technology and conventional method of casting. Sixteen frameworks in one-piece, were obtained from a metallic matrix containing three Brånemark compatible implants with regular platform (Titamax Cortical Ti, Neodent). Eight frameworks were fabricated by CAD / CAM system (NeoShape, Neodent): four in zirconia (ZirCAD) and four cobalt-chromium (CoCrcad). Eight other frameworks were obtained by conventional casting method: four cobalt-chromium with UCLA abutment premachined Co-Cr (CoCrUCci) and four cobalt-chromium with UCLA abutment castable (CoCrUCc). The fit vertical, horizontal and passivity by one-screw test were measured using scanning electron microscopy with magnification of 250x. Initially evaluated the passivity by one-screw test and subsequently to assess the vertical and horizontal misfit, tightened all the screws with a torque of 20 Ncm. Mean, standard deviation, minimum and maximum values were calculated for each group. Measurements of horizontal misfit were transformed into cumulative frequency for categorization of the variable and the group later comparison groups. To evaluate the existence of quantitative differences between the groups tested for vertical misfit and passivity, we used the Kruskal-Wallis test. The Mann-Whitney test was used to compare group to group statistical differences (p <0.05). Were observed the respective mean and standard deviation for vertical misfit and passivity in micrometers: ZirCAD (5.9 ± 3.6, 107.2 ± 36), CoCrcad (1.2 ± 2.2, 107.5 ± 26 ), CoCrUCci (11.8 ± 9.8, 124.7 ± 74), CoCrUCc (12.9 ± 11.0, 108.8 ± 85). There were statistical differences in measures of vertical misfit (p = 0.000). The Mann-Whitney test revealed statistical differences (p <0.05) between all groups except between CoCrUCci and CoCrUCc (p = 0.619). No statistical difference was observed for the passivity. In relation to the horizontal misfit groups ZirCAD and CoCrcad did not show best values in relation to CoCrUCci and CoCrUCc. Based on the results it can be concluded that frameworks fabricated by CAD / CAM technology had better values of vertical fit than those manufactured by the casting method, nevertheless, the passivity was not influenced by manufacturing technique and material used. The horizontal fit obtained by frameworks manufactured by CAD / CAM was not superior to those manufactured by casting. A lower variability in vertical adjustment and passivity was observed when frameworks were fabricated by CAD / CAM technology

Bolton freeware: aplicativo de avaliação de discrepância de massa dentária desenvolvido pelo programa de pós-graduação em odontologia/UFRN

The calculation of tooth mass discrepancy, essential for good planning and a proper orthodontic finishing, when performed manually, besides being laborious, requires considerable time consumption. The aim of this study was to develop and test Bolton Freeware, a software for analysis of the tooth mass discrepancy of Bolton, aiming to minimize the consumption of time in a less onerous way. The digital analysis of the software was done by means of two-dimensional scanning of plaster study models and compared to manual evaluation (gold standard), using 75 pairs of stone plaster study models divided into two groups according to the magnitude of the Curve of Spee (group I from 0 to 2 mm, group II greater than 2 to 3mm). All the models had permanent dentition and were in perfect condition. The manual evaluation was performed with a digital caliper and a calculator, and the time required to perform the analysis for both methods was recorded and compared. In addition, the software was evaluated by orthodontists regarding its use, by means of questionnaires developed specifically for this purpose. Calibration was performed prior to manual analysis, and excellent levels of inter-rater agreement were achieved, with ICC > 0.75 and r > 0.9 for total and anterior proportion. It was observed in the evaluation of error of the digital method that some teeth showed a significant systematic error, being the highest measured at 0.08 mm. The analysis of total tooth mass discrepancy performed by Bolton Freeware, for those cases in which the curve of Spee is mild and moderate, differ from manual analysis, on average, 0.09 mm and 0.07 mm respectively, for each tooth evaluated, with r> 0, 8 for total and anterior proportion. According to the specificity and sensitivity test, Bolton Freeware has an improved ability to detect true negatives, i.e. the presence of discrepancy. The Bolton analysis digitally performed was faster, with an average difference of time consumed to perform the analysis of Bolton between the two methods of approximately 6 minutes. Most experts interviewed (93%) approved the usability of the software

Avaliação da qualidade da atenção primária à saúde da criança no Rio Grande do Norte: visão das usuárias

The study aims to evaluate the quality of the work processes of the teams from the Family Health Strategy regarding the comprehensive health care for children, in the view of users in the state of Rio Grande do Norte. This is a cross-sectional observational evaluative research with quantitative approach. The primary data are part of the External Review from the Program of Improving Access and Quality of Primary Care (PMAQ) in 2012. 190 women were interviewed. The inclusion criteria was the presence in the clinic at the time of the survey, have attended the service in the last 12 months and be a mother or companion of a child up to two years old. A research protocol was developed in the dimensions of Growth and Development, Breastfeeding and nutrition, and health problems and its variables. The results revealed that mothers / companions who responded to the questionnaire 71% were aged between 18 and 35 years, 92.1% were literate, 96.3% had a monthly income and 62.6% received financial assistance from the government. As for the children, 39.4% were aged between 13 to 24 months. In promotion and prevention actions for children, 64.2% had consultation up to the 7th day of life, 91.1% underwent the screening test, 95.3% had a health handbook, 98.9% had a vaccine, 17.9% breastfed or breastfeed from 6 to 24 months. As for link and continuity of care, 86.8% of the children were accompanied by the same professional staff and 59.5% left with next consultation scheduled. In acute situations 42.4% of the children went to the health unit and 64% of these were attended. It is concluded that the actions involving prevention and health promotion of children in RN, are evaluated positively by the service users and meet the requirements of MS, as well as link and continuity of care. The weakness in access and reception of users is evident, indicating the need to adapt the service to the demand of health and planning actions to welcome all who seeks basic health unit-UBS