914 resultados para Paper-and-pencil questionnaires
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The surface free energy of conditioned-dentin is one of the factors that interfere with monomeric infiltration of the interfibrillar spaces. Saturation of the tooth matrix with different substances may modulate this energy and, consequently, the wettability of the dentin. To evaluate the influence of different substances used to saturate conditioned-dentin on surface free energy (SFE) of this substrate. Dentin blocks (4 × 7 × 1 mm, n = 6/ group), obtained from the roots of bovine incisors, were etched using phosphoric acid for 15 seconds, rinsed and gently dried. The surfaces were treated for 60 seconds with: ultra-purified water (H20-control); ethanol (EtOH), acetone (ACT), chlorhexidine (CHX), ethylenediaminetetraacetic acid (EDTA); or sodium hypochlorite (NaOCl). The tooth surfaces were once again dried with absorbent paper and prepared for SFE evaluation using three standards: water, formamide and bromonaphthalene. Analysis of variance (ANOVA) and Dunnet's tests (a = 0.05) were applied to the data. Ethylenediaminetetraacetic acid was the only substance that caused a change to the contact angle for the standards water and formamide, while only EtOH influenced the angles formed between formamide and the dentin surface. None of the substances exerted a significant effect for bromonaphtha-lene. In comparison to the control, only EDTA and NaOCl altered both polar components of the SFE. Total SFE was increased by saturation of the collagen matrix by EDTA and reduced when NaOCl was used. Saturation of the collagen matrix by EDTA and EtOH changed the surface free energy of the dentin. In addition, the use of NaOCl negatively interfered with the properties evaluated. The increase of surface free energy and wettability of the dentin surface would allow higher penetration of the the adhesive system, which would be of importance to the clinical success of resin-dentin union.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The oxidized cassava starch is widely used in various industrial sectors, the major textile, paper and more recently by the food industry due to its characteristics, such as expansion property to baking. This study aimed to develop a modification of cassava starch by reaction with hydrogen peroxide and lactic acid, with two different types of drying, in the sun and in oven dried, in order to develop the expansion with increase of carboxyl groups and to evaluate differences between the types of drying and compare them with Expandex® starch and pre-gelatinized. The results indicated an increase in the rate of expansion of the modified starch dry in the sun, however the results of the content carboxylic groups haven't indicated the relationship with their rate expansion.
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A time-and-motion study in wood processing of the Eucalyptus harvester's operational cycle was developed. The objective was to evaluate wood harvesters working under several site conditions. The research includes two kinds of harvesters while processing wood to supply paper and cellulose factories, as follows: a machine with twin tires and other one with large tracks, both connected to a different head harvester models. The forestry species were Eucalyptus saligna Smith and Eucalyptus grandis Hill ex Maiden, seven and eight years old, in slope terrains ranging from 0% to 10% degrees, under harvesting systems used by Votorantim and Suzano forestry companies, in São Paulo State, Brazi. Considering all field research, results disclosed that, for some conditions, both machines have shown mathematical correlation between some mechanical wood operation within the processing operational cycle and the saw logs production. All the mathematical correlations were found to express logarithmical models.
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There are some titles that, under a stealthy look, cause unrest and stir with our imagination. The text by Ana Maria Machado - Point to point - and the topic of a meeting at the University of Brasilia - READ: reading, teaching and reception - intertextualized in the act of reading are sufficiently provocative. Then, from them can emerge a form of ripping, as with a scalpel in a sheet of blank paper and drawing with the word. In this way of thinking, we may write our text, beginning by quoting an essay of Glawinski (1977), in which the author says that literary criticism has only recently become interested in reading, either as an object of reflection, or as a descriptive tool.
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We can know a people through their cultural and artistic assets. One of the many aspects of Japanese culture is origami, a fusion of the verb “oru”, which means folding, with the word “kami” meaning paper. In this communication, we describe the course “Origami and Kirigami: art and culture as a recreational and educational resource”. The course aimed to present these two oriental techniques based on paper and its potential as a source of entertainment and education, at the same time seeking to introduce cultural aspects of these arts of folding and/or cutting paper. This practice is more common than we realize, and is present in our day-to-day life when we perform actions such as folding clothes and papers, and making packages, amongst others. However, few are aware of the benefits that this folding brings to the fields of Arts, Mathematics, and Science, besides its recreational characteristics. Kirigami is a mixed technique that in addition to using folds in the paper (as in origami) also uses cuts (“kiru” – meaning, “cut”). It can be performed with heavier paper than origami, and by introducing some cuts, the paper can be folded to form the desired shape. It is a simple technique, with impressive results. We conducted eight weekly meetings, each lasting four hours, totaling 32 hours of coursework. In addition to the classes, a visit was made to the Okinawa Club in Bauru (São Paulo), where it was possible for the students of the course and the elderly group (fujinkai) of origamists of the club to exchange experiences. Finally, an exhibition was organized to display the artifacts produced by the course participants and disseminate the work of the students.
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Pós-graduação em Ciência Florestal - FCA
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Pós-graduação em Ciência Florestal - FCA
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The species Artemisia annua L. (Asteraceae) is native to China and has artemisinin as its main active component, substance that is considered a potent antimalarial drug. With the increased interest in natural active principles, studies related to post-harvest and storage of vegetable material become important for better conservation of its phytotherapic properties. Therefore, the present study had as objectivedefine the best storage conditions to preserve and keep the quality of phytotherapic drugs. Leaves of A. annua dried were stored for six months in polyethylene bags wrapped in Kraft paper and packed in four treatments: at ambient condition, refrigerated at 4 ± 2 oC, using normal packing, and using vacuum packing. Samples were taken for microbiological, moisture content, and level of artemisinin analyses before the experiment begun and at 30, 90, 120 and 180 days. The results of microbiological tests showed no significant contamination, as well as the moisture content of the stored (biological) material, which remain between 5% and 10%, keeping within acceptable parameters. The ambient without vacuum treatment (SVA) was the treatment that better maintained the sample stability during 180 days, however, the refrigerated without vacuum (SVR) showed greater efficiency to conserve the content of artemisinin.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Ensino de Física - FCT
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Pós-graduação em Educação - FFC
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Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)