311 resultados para Variance analysis


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Purpose: The aim of this study was to evaluate the surface roughness of four packable composite resins, SureFil™ (Dentsply, Petrópolis, Rio de Janeiro, Brazil), Prodigy Condensable™ (Kerr Co., Orange, CA, USA), Filtek P60™ (3M do Brasil, São Paulo, Brazil), and ALERT® (Jeneric/Pentron, Inc., Wallingford, CT, USA) and one microhybrid composite resin (Filtek Z250™, 3M do Brasil) after polishing with four finishing systems. Materials and Methods: Twenty specimens were made of each material (5 mm in diameter and 4 mm high) and were analyzed with a profilometer (Perthometer® S8P, Perthen, Mahr, Germany) to measure the mean surface roughness (Ra). The specimens were then divided into four groups according to the polishing system: group 1 - Sof-Lex™ (3M do Brasil), group 2 - Enhance™ (Dentsply), group 3 - Composite Finishing Kit (KG Sorensen, Barueri, São Paulo, Brazil), and group 4 - Jiffy Polisher Cups® (Ultradent Products, Inc., South Jordan, UT, USA). The specimens were polished and then evaluated for Ra, and the data were subjected to analysis of variance, analysis of covariance, and Tukey's test (p = .05). Results: The mean Ra of SureFil polished with Sof-Lex was significantly lower than that of KG points. Prodigy Condensable polished with Enhance showed a significantly less rough surface than when polished with Sof-Lex. Filtek P60 did not exhibit a significant difference with the various polishing systems. For ALERT the lowest mean Ra was obtained with Sof-Lex and the highest mean Ra with KG points. Regarding Filtek Z250, polishing with KG and Jiffy points resulted in a significantly lower mean Ra than when polished with Enhance. Conclusions: Packable composite resins display variable roughness depending on the polishing system used; the Sof-Lex disks and Jiffy points resulted in the best Ra values for the majority of the materials tested.

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The hybrid Mentha pulegium x spicata, also well-known as poejo de praia, it is a perennial, low plant, with fields, violet stem and opposite leaves, with lance format and sawed board, presenting characteristic smell. The objective of the present work was accomplish a study of the leaf anatomy, including a biometric study of tissue and quantitative analysis of secretory trichomes/mm2 and of stomata/mm2 in both faces of the epidermis, besides a chemical analysis of the essential oil. Histological permanent laminas were made for anatomical analysis of the leaf surface and also sheets of the impression to foliate for the count of the trichomes number and stomatas. The chemical studies were made through the extraction of the essential oil by hydrodistillation and analyzed in GC-MS. The capitate and peltates trichomes are present on both sides of the leaf, even so they prevail in the abaxial surface. The variance analysis show that there are significant differences for the number of capitate trichomes and tectores between the adaxial and abaxial surfaces, but they are not significant for the peltate trichoma. The analyzed of essential oil shows the presence of a majority component, trans piperitone epoxide, being it responsible for more than 80% of the relative composition in the essential oil.

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The objective of this work was to evaluate different concentrations of nutritional solution in the hydroponic cultivation of Viola x wittrockiana Gams. The experiment was conducted in DFT hydroponic system, in a completely randomized design with a 5×4 factorial scheme and five nutrient solution concentrations (50, 75, 100, 125 and 150%), four evaluation periods with three replications of three plants for each treatment. Plant height, root length, number of leaves, flowers and floral buttons; fresh and dry weight of shoot and root were determined. The results were submitted to variance analysis, Tukey's test for evaluation periods and regression analysis for nutrient solution. A decrease in the development of the shoot and root was observed with an increase of the number of cultivation days; the greatest number of floral buttons occurred in the third week of cultivation. A reduction in the plant height, root system length, the number of leaves and the fresh and dry weight of shoot was observed generally with the increase of nutrient solution concentration.

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Objective: The purpose of this study was to compare the accuracy of two working cast fabrication techniques using strain-gauge analysis. Methods: Two working cast fabrication methods were evaluated. Based on a master model, 20 working casts were fabricated by means of an indirect impression technique using polyether after splinting the square transfer copings with acrylic resin. Specimens were assigned to 2 groups (n=10): Group A (GA): type IV dental stone was poured around the abutment analogs in the conventional way; Group B (GB), the dental stone was poured in two stages. Spacers were used over the abutment analogs (rubber tubes) and type IV dental stone was poured around the abutment analogs in the conventional way. After the stone had hardened completely, the spacers were removed and more stone was inserted in the spaces created. Six strain-gauges (Excel Ltd.), positioned in a cast bar, which was dimensionally accurate (perfect fit) to the master model, recorded the microstrains generated by each specimen. Data were analyzed statistically by the variance analysis (ANOVA) and Tukey's test (α= 5%). Results: The microstrain values (με) were (mean±SD): GA: 263.7±109.07με, and GB: 193.73±78.83με. Conclusion: There was no statistical difference between the two methods studied.

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Tha aim of this study was to evaluate the thermocycling effect on microhardness of laboratory composite resins, 30 disks were fabricated, 5mm of diameter and 2mm of width, using 3 laboratory resins: G1 (n=10) - RESILAB MASTER (Wilcos-Brasil), G2 (n=10) - Vita VMLC (VITA Zahnfabrik-Germany), and G3 (n=10) - Vita Zeta (VITA Zahnfabrik-Germany). Vickers microhardness (HV) of all specimens was evaluated using a microhardness tester FM-700 (Future Tech- 50 g/10s). The specimens were measured before and after the thermocycling (3,000 times and 12,000 times - 5°/55°C±1). The microhardness values before cycling were (mean±SD): G1: 55.50±4.6; G2: 35.54±2.5; G3: 27.97±1.6; after 3,000 thermocycles: G1: 55.54±3.9; G2: 29.92±2.73; G3:21.01±1.4 and after 12,000 cycles G1: 54.27±3.2; G2: 30.91±1.6; G3: 23.81±0.9. Variance analysis (ANOVA) and Tukey's test was accomplished (p<0.05), the highest microhardness values were observed in G1: G2 and G3 showed reduction of microhardness values. It was concluded that, after thermocycling, the tested laboratory composites resins are susceptible to the decrease of surface microhardness.

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The pressure caused by agricultural machinery traffic many result in soil compactation in no-tillage system. The aim of this work was to evaluate no-tillage system onset,time on some physical properties, index S and organic matter (OM) of an oxysol located in Jaboticabal, Sao Paulo State, Brazil. The experiment had completely randomized split-splot design. The treatments consisted of four no-tillage systems: no-tillage for 2 years, no-tillage for 4 years, no-tillage for 6 years and one natural wooded area. The evaluated layers were: Q-0.10m, 0.10-0.20m and 0.20-030m. The following were determined: soil porosity, soil aggregates, bulk density, index S and organic matter. The results were submitted to variance analysis and when there was a difference between averages, Tukey's test was used to compare them. The natural wooded area showed higher organic matter, macroporosity, hydraulic conductivity and Index S. There was no difference between the studied parameters, showing that the no-tillage system for six years was not enough to change the soil physical property.

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Present study aimed to evaluate gonadotropins profiles in 12 Nelore heifers, in order to test the hypothesis that FSH concentrations decrease and LH presents a transient increase during follicle selection. Blood samples from jugular vein were harvested twice daily starting at the time of ovulation (D0) until D5. Plasma samples were assayed for FSH and LH by double antibody radioimmunoassay method. LH and FSH assay sensitivity was 0,02ng/ml and 0,005ng/ml, respectively. The intraassay coefficient of variation was 13,6% and 18,8%, respectively. Data (mean±SEM) were normalized to follicle deviation and analyzed by ANOVA and by linear, cubic, and quadratic regressions. Comparisons between higher and lower FSH values were also performed by T-test. There was no effect of time in plasmatic FSH and LH circulating levels when variance analysis or regression analysis were performed. However, by T-test, FSH concentrationsreached the lowest plasmatic levels 36 (0,40±0,05ng/ml) and 60 hours (0,42±0,04ng/ml) after follicular deviation, comparatively to 36 hours before deviation, when the concentrations were maximal (0,63±0,08ng/ml). In conclusion, there is a FSH decrease, although a transient LH elevation has not been confirmed encompassing follicle deviation in Nelore females.

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This work was conducted throughout three phases of swine's growth (7 days from birth till the weaning age; from weaning until 7 days later and from 8 to 21 days after weaning); taking as objective the evaluation of the development of suckling and weaned piglets fed with a bran or extruded, dried and wet diet. We've used, for this paper, a total number of 31 pigs breeds, weaned and in average 21 day's lifetime and 3 different rations: dried bran; dried extruded bran and wet extruded bran (2 volumes of water to one volume of ration). During the 8th and 21st day after weaning all the animals received the same bran dried ration. Water and ration were supplied ad libitum. The experimental delimitation was totally random, with 3 treatments and eleven repetitions in the two first phases and five repetitions in the third phase, the multivariate variance analysis applied in the inferences about the results and from this we could conclude that the weight daily gain and the ration daily consumption were significantly not affected, i.e. by the processing, by the dry material ration content. However, we could observe a tendency to increase ration consumption and weight gaining when the animals were fed with bran extruded wet ration.

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One of the greatest challenges faced by buccomaxillofacial prosthetists is to reproduce the patient's exact skin color and provide adequate esthetics. To reach this objective, professionals must use materials with easy characterization and that maintain color over long periods of time. The objective of this study was, thus, to evaluate the color stability of two types of silicones, Silastic 732 and Silastic MDX4-4210. Twenty-four test specimens were made from each type of silicone and were divided into a colorless group and groups intrinsically pigmented with ceramics, cosmetics or iron oxide. The specimens were submitted to an accelerated system of aging for non-metallic materials. Readings were carried out initially and after periods corresponding to 163, 351, 692 and 1,000 hours of aging, using a reflection spectrophotometer analysis, and color alterations were calculated by the CIE L*a*b* system. The data were submitted to variance analysis and Tukey's test at a 5% level of probability. The results demonstrated that, irrespective of the period of time analyzed, all the materials underwent some type of chromatic alteration (ΔE > 0). The test specimens made with Silastic 732 and MDX4-4210, without pigmentation, presented the lowest color alteration values after 1,000 hours of aging. Of the pigments, ceramic presented the lowest color alteration values and cosmetic powder presented the highest values. Thus, it may be concluded that the materials without the incorporation of pigments presented similar color alteration values, and did not differ statistically. The cosmetic powder used in this study was the pigment that most altered the color of the test specimens. © 2009 Sociedade Brasileira de Pesquisa Odontológica.

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The aim of this study was to evaluate the influence of different periods of rainfall that occurred after the application of the imazapyr herbicide on the control efficiency of Pistia stratiotes and Eichhornia crassipes. We studied 10 mm rainfall, applied for 5' at different time periods (0h, 2h, 4h, 6h, 8h, 12h, 24h, not simulated rainfall) after the application of imazapyr formulation Arsenal NA, 250 g ai ha -1 (1.0 L cp ha -1). The experiment had completely randomized design with four replications. Plants were evaluated at 7, 14, 21, 28 and 35 days after application (DAA), and the results submitted to analysis of variance by F test and treatment means compared by Tukey's test (p <0. 05). The occurrence of rainfall up to 6 hours after herbicide application, plants of P. stratiotes, negatively affected its efficiency and control; rainfall intervals over 8 hours had no effect in control. The occurrence of rainfall at all time intervals did not affect the control of E. crassipes plants.

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The aim of this research was to evaluate the white mold severity (Sclerotinia sclerotiorum (Lib.) of Bary), bean production components and yield (Phaseolus vulgaris L.), variety Perola, according to the application of procimidone fungicide (Sialex 500), through fungigation (center pivot) and automotive sprayer (Uniport). The study was carried under field production commercial conditions, in Primavera do Leste - MT - Brazil. The experiment consisted of 5 treatments (with 4 repetitions of 4 ha each), all with two procimidone applications (1.2 kg ha-1 each application, same as, 0.6 kg a.i. per hectare) to the 42 and 52 days after seeding. The water depths of 5.5 and 11.0 mm were tested in the application through central pivot (this had your checked uniformity), providing volumes of 55.000 and 110.000 L ha-1, respectively, and the volumes of 120 and 200 L ha-1 in the automotive sprayer. The severity of disease was evaluated by the percentage of the area affected by plant damage using diagramatic grade scale of white mold severity, as described by Azevedo (1998). The values were used to calculate the area under the disease progress curve (AUDPC). They were also analyzed, the number of the fungus apothecia during the crop cycle and the residual sclerotias weight in harvest. On this occasion, it was also evaluated the crop yield parameters: number of plants per plot (final stand), pods per plant, grains per pod, medium weight of 200 grains and productivity of grains. The AUDPC values, apothecia to 42, 49 and 56 days after seeding, sclerotias in 2 soil kg and the crop productivity parameters were submitted to the variance analysis and Tukey Test at 0.05 of probability. This test was also applied in the comparison among the different fungicide application methods, independent of spray volumes in each one. The statistical processing was accomplished by STAT program. The results showed that weren't differences among application techniques studied in relation to productivity parameters, however, best white mold control, smaller apothecia number to 49 and 56 days after seeding and smaller weight of residual sclerotias in the harvest were obtained with the fungigation, independently of the spray volume used.

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Sensory characteristics of Morada Nova lambs meat (muscles Biceps femoris, Longissimus and Triceps brachii) submitted to effects of ageing and injection of calcium chloride were studied. The lambs were slaughtered at 25 kg of body weight. After rigor mortis, muscles were removed and submitted to treatments. The variance analysis indicated that ageing and calcium chloride didn't influence the attributes flavor (6.71) and tenderness (7.13) of meats from Biceps femoris. The interaction among the factors wasn't significant for tenderness, however it was significant for flavor. Ageing didn't affect colour (7.08), flavor (7.42), tenderness (7.83) and global impression (7.58) of meats from Longissimus without calcium chloride, and meats with calcium chloride also didn't affect. Ageing and calcium chloride factor didn't influence the attributes flavor and tenderness of meats from Triceps brachii. The interaction among the factors wasn't significant for attributes flavor and tenderness. The sensory quality of Morada Nova lambs meat, was shown similar with relationship to evaluated attributes when it was submitted to ageing and injection with calcium chloride.

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This work was carried out to evaluate the effects of sugarcane straw density and positions of seeds of Euphorbia heterophylla, Mucuna cinereum, Digitaria nuda and Eleusine indica on emergence and initial development of plants. The experiment were arranged in a completely randomized design, with 15 treatments and four replications, in a factorial arrangement 3 x 5 with a additional control; the first factor was constituted by position of seeds related to the straw (under, between and on) and the second by five quantities of straw (1, 2, 4, 8 e 16 t ha -1) with a control without straw. At 15 days after sowing (DAS) it was realized evaluations of height, dry mass and emergence percentage for E. heterophylla and M. cinereum, and at 28 DAS it was analyzed dry mass and emergence percentage for D nuda e E. indica. Data obtained were submitted to F in variance analysis test and means were compared with Tukey at 5% probability. Emergence and initial development of E. heterophylla e M. cinereum were reduced with increasing of straw and were affected by seed position, but it was not inhibited in none of conditions, indicating aggressiveness of these weeds in sugarcane mechanized harvest conditions. D. nuda and E. indica emergence was not affected by seed position and coverage soil with 8 e 16 t ha -1 of sugarcane straw inhibited its emergence.

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Este trabalho teve por objetivo estudar a variação de vazão em tubogotejadores NaanPC laranja e NaanPC azul em função de precipitados químicos, ao longo do tempo de funcionamento, quando submetidos a uma água rica em ferro, avaliando-se especificamente o coeficiente de uniformidade de Christiansen (CUC) e o coeficiente de uniformidade de distribuição (CUD). O experimento foi desenvolvido em uma bancada de ensaios para tubogotejadores no Laboratório de Ensaio de Equipamentos para Irrigação do Departamento de Engenharia Rural da Faculdade de Ciências Agronômicas - UNESP, localizado no município de Botucatu – SP. O experimento foi montado em esquema fatorial 2x2x7, sendo duas doses de Fe, dois modelos de gotejadores e sete tempos de funcionamento, com três repetições, totalizando 84 parcelas experimentais. Efetuou-se a análise de variância pelo teste F. As médias das vazões dos gotejadores foram comparadas pelo teste de T de Student a 5% de probabilidade. Os resultados obtidos não apontaram diferença significativa nas diferentes doses de ferro. Entretanto, os resultados apontaram diferença significativa na interação gotejador x tempo e coeficiente de uniformidade de Christiansen (CUC).

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Bean (Phaseolus vulgaris L.) is widespread in the Brazilian social and economic scene. The hypothesis is that if the water supply is suppressed in just one of the five development stages of irrigated beans, it can result in yield reduction lower than 20%, allowing water economy. The objective of this study was to compare the performance of bean Carioca group IAC Alvorada yield components, with irrigation suppression in each of the five phenological phases (emergence, vegetative, flowering, grain filling and maturation) and no irrigation and irrigated in all stages. The study was conducted at Agronomical Sciences College, UNESP, Botucatu, SP, Brazil. The statistical design was the randomized block with seven treatments and four replications. Data were subjected to analysis of variance and t test at 5% probability. A rainfall event (58 mm) after planting allowed the successful emergence of seedling beans in plots where water would not be applied. The yield components were higher affect when there was irrigation's suppression at Vegetative phase and at Flowering phase. The treatments where occurred irrigation suppression at Maturation and at Emergence showed yield reduction of less than 20%, proving the hypothesis.