Resumo Objetivo: este estudo investigou o efeito das condições de lubrificação no atrito entre braquetes e fios de NiTi de diferentes secções transversais. Métodos: os braquetes (Roth, GAC) foram fixados a um dispositivo conectado a uma máquina de ensaio universal, que recebeu segmentos de fio de NiTi (Nitinol, GAC) com secções de 0,012”; 0,016” ou 0,020”. Após o fio ter sido instalado no slot do braquete, aplicou-se um dos seguintes lubrificantes: saliva humana (SH: controle positivo), água destilada (AD) ou saliva artificial à base de mucina (MUC) ou de carboximetilcelulose (CMC). No grupo controle negativo, nenhum lubrificante foi utilizado. As combinações entre as secções dos fios e as condições de lubrificação geraram 15 grupos, com 15 amostras cada. Os dados foram submetidos à análise de variância a dois critérios e ao teste de Tukey. Resultados: não houve interação significativa entre a secção do fio e a condição de lubrificação (p = 0,901). Independentemente de ter sido utilizado ou não lubrificante, observou-se elevação significativa do atrito com o aumento da secção transversal do fio (p < 0,001). Para qualquer um dos fios, o grupo testado na presença de MUC não diferiu daquele em que se aplicou SH. Por outro lado, quando suprimiu-se os lubrificantes, constatou-se atrito significativamente mais elevado. Os grupos CMC e AD demonstraram comportamento intermediário. Conclusões: o atrito se elevou com o aumento da secção transversal dos fios de NiTi, mas a despeito do fio, o atrito com a saliva à base de MUC foi similar àquele com a SH e menor do que sob condição a seco.

Abstract Objective: This study investigated the effect of the condition of lubrication on the friction between brackets and NiTi archwires of different rounded cross-sections. Methods: Brackets (Roth, GAC) were affixed to a device connected to a universal testing machine into which segments of archwire were placed (NiTi, Nitinol, GAC) with cross-sections of 0.012-in, 0.016-in and 0.020-in. Once the wire was in the bracket slot, the following lubricants were applied: human saliva (HS: positive control), distilled water (DI), mucin-based (MUC) or carboxymethylcellulose-based (CMC) artificial saliva. In the negative control group, no lubricant was used. The combination between the wire cross-sections and the lubrication condition generated 15 groups with 15 samples each. Data were submitted to two-way analysis of variance and Tukey’s test. Results: There was no significant interaction between the wire cross-section and the condition of lubrication (p= 0.901). Irrespective of whether lubricants were used or not, there was a significant increase in friction with an increase in the cross-section of the wire (p< 0.001). For any wire, the group tested in the presence of MUC was not different from that in which HS was applied. On the other hand, when the application of lubricants was suppressed, significantly higher friction values were observed. The CMC group and the DI group demonstrated intermediate behavior. Conclusions: Friction increased with the increase of the cross-section of the NiTi archwire, but regardless of the archwire, friction with MUC artificial saliva was similar to that of HS and lower than in dry conditions.

Abstract Drilling fluids are multicomponent systems used to aid the removal of cuttings from a borehole, and subject to a number of requirements to ensure a safe drilling operation. One of the most important is to form a low permeability cake on the walls of the hole penetrated by the bit, to avoid excessive filtrate loss. To that end, carboxymethylcellulose (CMC) associated with calcite (CaCO3) can be used. In this paper, the effect of carboxymethylcellulose on the colloidal properties of calcite suspensions in brine was systematically evaluated by rheological properties, filtrate volume and zeta potential. Higher viscosity fluids, lower filtrate loss and less negative zeta potential were obtained using small calcite particles with wide size distribution and CMC with high average molecular weight (Mw) and low average degree of substitution (DS), highlighting the importance of effective interactions between CMC and calcite to improve drilling fluid properties.

Abstract Orally disintegrating films (ODF) produced with a hydrophilic polymers are a thin and flexible material, wich disintegrate in contact with saliva and can vehicule bioactive materials. The aim of this study was to develop and characterize ODF formulation with potential to act as a carrier for different bioactives compounds prepared with low cost polymers. Gelatin (G), starch (S), carboxymethyl cellulose (CMC) and their blends (G:S, CMC:S, CMC:G, and CMC:S:G) were prepared by casting technique with sorbitol as a plasticizer. The formulations were characterized in terms of visual aspects, FTIR, SEM, mechanical characteristics, hygroscopicity, dissolution (in vitro and in vivo) and swelling index. FTIR analysis revealed that no interaction between polymers in ODF was observed. By SEM, it was possible to observe differences on surfaces by different polymers. ODF made with CMC and CMC:G presented higher water absorption (P<0.05) and higher swelling index probably due to the higher water affinity by CMC. Formulations with G, CMC:G and CMC:S:G presented the highest values of tensile strength (P<0.05). ODF prepared with S alone presented the highest disintegration time, the others formulations showed in vitro dissolution ranging from 5.22 to 8.50 min, while in vivo dissolution time ranged from 2.15 to 3.38 min. By the formulations made with G and blend of G:S and CMC:S:G it is possible to develop a ODF of low cost with desired characteristics being an alternative vehicle to deliver functional compounds for continuous use.

ABSTRACT An experiment was conducted to compare three nutritional programs, which were developed with tannin-free grain sorghum based diets, evaluating performance, carcass yield and bromatological composition of the pectoral muscle of broilers. A total 1360 chicks mixed (50:50), from one to 42 days old Hubbard Flex Broilers, were housed in a completely randomized design consisting of treatments and 10 replicates each, distributed as follows: three programs with whole sorghum grain based diets (nutritional program with daily adjustment, nutritional program with every three days adjustment and nutritional program with four stages and a program with ground and whole sorghum grain based feed (four stages). The cumulative performance was evaluated at, 21 and 42 days, determining feed intake, weight gain, feed conversion and viability. At 42 days, the yield of eviscerated carcass, breast (full and boneless), thighs/drumsticks and wings and breast composition were evaluated. Nutritional adjustments showed better feed conversion, did not affect the carcass, commercial cuts yield and had a good breast meat quality. It can be concluded that daily feed programs could be performed in poultry industry with the mixture of whole sorghum grains and concentrates directly on farms contributing to better logistics and feed transportation cost.

ABSTRACT The objective of the study was to evaluate the effect of nutritional plans on the productive and economic performance of Hubbard Flex broiler chickens. A completely randomized experimental design was applied, consisting of five treatments. Treatments consisted of five different nutritional plans: a basal diet containing the nutrient and energy levels recommended by literature and designated reference diet; two diets containing 1.5% and 3% lower levels than the reference diet; and two diets containing 1.5% and 3% higher levels than the reference diet (-3%, -1.5%, reference plan, +1.5% and +3%). Feed intake (FI), body weight (BW), feed conversion rate (FCR), livability (L) and productive efficient index (PEI) were determined when broilers were 42 days old. Broilers were processed, and carcass and parts (breast fillet, leg, and wings) yields were determined. The economic viablility of the nutitional plans was evaluated as a function of feed cost/kg live and carcass weights, economic efficiency index (EEI), and cost index (CI). Feed intake and the feed conversion rate decreased as dietary nutrient and energy levels increased. Feed cost/kg live weight, economic efficiency index, and cost index cost increased as dietary nutrient and energy levels increased. Feed intake, feed conversion ratio, production efficiency index, and breast yield improved with increasing nutritional and energy levels. However, worse economic results were obtained with higher nutritional and energy levels.

The aim of this study was to evaluate the incidence of footpad dermatitis and quality of broilers litter fed with sorghum grain and diets based in corn. It was used 544 male and female chicks, distributed in a completely randomized design with two treatments and eight replications. The chicken feed was formulated and produced from corn, soybean meal and sorghum grain. In the formulation were kept constant levels of energy and protein in accordance with the following treatments: A. Control (diet based on corn and soybean meal); B. Grain sorghum (Whole Sorghum + soybean meal). At 35 and 42 days were evaluated mineral matter (A %), calcium (Ca%), phosphorus (P%), pH and dry matter (DM %) of the poultry litter. To evaluate the footpad dermatitis were evaluated eight feet per treatment by visual analysis. At 35 and 42 days of age DM % MM (%), Ca (%) P (%) and pH of poultry litter no difference (p>0.05) was found between the treatments and the type of ingredient in the birds' diet is not related (p>0.05) with the incidence of footpad dermatitis. The incidence of footpad dermatitis and the quality of the litter weren't influenced by the type of the ingredient used in diet.

The objective of this study was to evaluate the performance and carcass characteristics of broilers fed exclusively vegetable diets and diets containing animal meal with the addition of creatine or not after day 8. In the experiment, 1080 one-day-old male chicks were distributed according to a completely randomized experimental design into six treatments with six replicates each. A control diet based on corn and soybean meal was formulated, to which animal meals and creatine were included or not. Diets were formulated to contain equal mineral (calcium, phosphorus and sodium) and amino acid (available methionine + cystine, lysine and threonine) levels. The following treatments were applied: A. control (diet based on corn and soybean meal); B. control + creatine (600g/ton); C. inclusion of 5% meat and bone meal (MBM), D. inclusion of 5% MBM + creatine (600g/ton), E. inclusion of 5% blood meal (BM), F. inclusion 5% BM + creatine (600g/ton). Weight gain, feed intake, feed conversion, carcass yield and viability were evaluated. At 42 days of age, BM dietary inclusion impaired weight gain and feed conversion ratio. The inclusion of MBM affected only feed conversion ratio. The addition of creatine ito the diet with BM improved weight gain when compared with the BM diet with no creatine. The addition of creatine to the diet containing 5% BM improved weight gain when compared with the same diet without the use of the additive.

The combined effect of hydroxypropyl-β-cyclodextrin (HPβCD) and polyvinylpyrrolidone (PVP) or sodium carboxymethylcellulose (CMC) on the solubility of pyrimethamine (PYR) was studied. Equimolar PYR-HPβCD solid systems, in the presence or the absence of 0.25% (w/v) PVP or 0.10% (w/v) CMC were prepared by coevaporation or freeze-drying, and characterized by differential scanning calorimetry, X-ray diffraction analysis and dissolution profile. Phase-solubility analysis was used to investigate the interactions in aqueous solution between PYR and HPβCD, in the absence or presence of polymers, which showed a linear increase of PYR solubility depending on the concentration of HPβCD. The presence of polymer did not alter the stoichiometry of the complexes. DSC results were indicative of complexation, due to the loss of the characteristic endothermic peak of PYR. X-ray diffraction analysis confirmed the DSC results. Binary and ternary complexes showed higher dissolution rate when compared with the pure drug.

Na preparação de molhos de salada substitutos da maionese, para reduzir a quantidade de ovos e de óleo são utilizados emulsificantes e espessantes associados ou não à proteína de soja. Neste trabalho, o extrato de soja integral homogeneizado foi utilizado como base para a preparação de emulsão cremosa para substituir a maionese. O extrato de soja foi elaborado com teor de sólidos totais de 6 a 12%, após cozimento em água com bicarbonato, trituração e homogeneização a alta pressão. A emulsão preparada com diversas proporções de extrato de soja e óleos de soja e girassol foi também submetida à homogeneização a alta pressão variando de 1000 a 4000 psi. Na formulação do molho cremoso foram utilizados: açúcar, sal, ácido cítrico e diferentes hidrocolóides como estabilizantes. Os produtos foram avaliados quanto às características nutricionais, sensoriais, reológicas e de estabilidade. As condições mais favoráveis quanto à estabilidade e comportamento reológico para obtenção de molho cremoso foram atingidas quando se utilizou extrato de soja com 10% de sólidos, pressão de homogeneização de 3000 psi e relação extrato:óleo de 70:30, condição que apresentou redução de calorias de até 60%, em relação à maionese. Não foi observada diferença significativa (p < 0,05) quanto à preferência em relação ao sabor e consistência, bem como considerando a intenção de compra para as amostras de molho cremoso preparadas com os óleos de soja e girassol, utilizando-se como estabilizantes a goma xantana, maltodextrina ou carboximetilcelulose. O produto final é livre de colesterol, apresenta a vantagem do maior conteúdo proteico e teor reduzido de óleo e de calorias, além de adequada aceitação pelo consumidor, em relação à maionese tradicional e molhos para saladas.

The salad dressing preparation, which replaces for replacing the mayonnaise, uses utilizes emulsifiers and thickeners related or not to the soy protein in order to reduce the egg and oil quantity. In the The present work, used homogenized whole soymilk was used to prepare a creamy low-fat emulsion to replace traditional mayonnaise. The whole soymilk was elaborated with 6-12% of solids after cooking with bicarbonate, grinding and homogenizing it under high pressure. The emulsion was prepared with several proportions of soymilk and sunflower and soybean oils and was also submitted to high-pressure homogenization, under high pressure, which varied from 1000 to 4000 psi. Sugar, salt, citric acid and different hydrocolloids were used in the creamy sauce formulation as stabilizers. The products were evaluated according to their nutritional, sensory and physical properties (stability and viscosity). The more favored conditions regarding the stability and rheological behavior of the creamy low-fat emulsion were reached with 10% of solids, at 3000 psi and the proportion of 70:30 soymilk:oil (v/v). The product underfrom such conditions presented a calorie reduction of up to 60% compared to the mayonnaise. No significant difference was observed (p < 0.05) on consumer flavor and consistency acceptance, norneither in relation to the purchase intention of the samples prepared with soybean and sunflower oils, and xanthan gum, maltodextrine or CMC as thickener agents. The final product is cholesterol free and has the advantage of a higher protein content, reduced oil and calories, in addition tobesides an adequate consumer acceptance when compared to traditional mayonnaise and other salad dressings.

Molecular probe techniques have made important contributions to the determination of microstructure of surfactant assemblies such as size, stability, micropolarity and conformation. Conductivity and surface tension were used to determine the critical aggregation concentration (cac) of polymer-surfactant complexes and the critical micellar concentration (cmc) of aqueous micellar aggregates. The results are compared with those of fluorescent techniques. Several surfactant systems were examined, 1-butanol-sodium dodecylsulfate (SDS) mixtures, solutions containing poly(ethylene oxide)-SDS, poly(vinylpyrrolidone)-SDS and poly(acrylic acid)-alkyltrimethylammonium bromide complexes. We found differences between the cac and cmc values obtained by conductivity or surface tension and those obtained by techniques which use hydrophobic probe.