848 resultados para Extruded plastic scintillator
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The effects of exogenous enzymes supplementation on kibble diets for dogs formulated with soybean meal (SBM) as a substitute for poultry by-product meal (PM) was investigated on nutrient digestibility, fermentation products formation, post-prandial urea response and selected faecal bacteria counts. Two kibble diets with similar compositions were used in two trials: PM-based diet (28.9% of PM; soybean hulls as a fibre source) and SBM-based diet (29.9% of SBM). In experiment 1, the SBM diet was divided into three diets: SBM-0, without enzyme addition; SBM-1, covered after extrusion with 7500U protease/kg and 45U cellulase/kg; and SBM-2, covered with 15000U protease/kg and 90U cellulase/kg. In experiment 2, the SBM diet was divided into three diets: SBM-0; SBM-1, covered with 140U protease/kg; 8U cellulase/kg, 800U pectinase/kg, 60U phytase/kg, 40U betaglucanase/kg and 20U xylanase/kg; and SMB-2, covered with 700U protease/kg, 40U cellulase/kg, 4000U pectinase/kg, 300U phytase/kg, 200U betaglucanase/kg and 100U xylanase/kg. Each experiment followed a block design with six dogs per diet. Data were submitted to analysis of variance and means compared by orthogonal and polynomial contrasts (p<0.05). In both experiments, nutrients and energy digestibility did not differ between diets (p>0.05). SBM consumption resulted in increased faecal moisture and production (p<0.05), without effect on faecal score. Higher concentration of propionate, acetate and lactate, and lower ammonia and pH were found in the faeces of dogs fed SBM (p<0.05). Higher post-prandial urea was verified in dogs fed SBM (p<0.05). In experiment 2, the addition of enzymes increased faecal concentration of propionate, acetate and total short-chain fatty acid (p<0.05) and tended to reduce post-prandial urea concentration (p=0.06). Although with similar digestibility, SBM shows a worse utilization of absorbed amino acids than the PM. Soybean oligosaccharides can beneficially change gut fermentation product formation. Enzymes can increase the gut fermentation activity and improve the SBM proteic value. © 2013 Blackwell Verlag GmbH.
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We analyzed the differences between irrigated and non-irrigated plants of three congeneric Styrax species that present distinct distribution patterns in the physiognomies of the Cerrado vegetation in Brazil. Styrax ferrugineus showed a stomatal conductance (gs) unresponsive to soil water deficit in potted plants. This may explain the high gas exchange and photochemical efficiency found in this species, which is well adapted to the Cerrado sensu stricto (s. str.), a savanna-type vegetation. S. camporum, which is widely distributed in the Cerrado sensu lato (s. l.) areas, was the only species that exhibited increased intrinsic water use efficiency on the days of maximum water deficit. This result distinguishes S. camporum from S. pohlii, which is a forest species, since the gs of both species decreased during the days of maximum water stress. In contrast to other studies, we propose that instantaneously measured traits, such as leaf gas exchange rates and chlorophyll fluorescence, may be used to detect non-plastic performances in response to environmental stress, helping explain distinct geographical distributions of congeneric species in the Cerrado vegetation. © 2013 Springer-Verlag Berlin Heidelberg.
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Instrumental texture analysis on extruded snacks is widely applied, however there is no scientific consensus about the test and probe types that can be correlated with the sensory texture of snacks. Eleven commercial extruded snacks of different shapes were evaluated instrumentally using different probes and sensorially through descriptive analysis. The snack texture was described using the attributes of hardness, crispness, adhesiveness, fracturability and chewiness. Cylindrical snacks were described through crispness and fracturability, pelleted and shell-shaped snacks by chewiness and ring-shaped snacks by adhesiveness and hardness. Hardness and adhesiveness were correlated with a Warner-Bratzler test using a V shape probe (r = 0.718 and r = 0.763, respectively), while fracturability and chewiness were correlated with a Warner-Bratzler test using a guillotine (r = 0.776 and r = 0.662, respectively). The fairly strong good correlations enable application of these instrumental tests as an indication of the sensory texture of extruded snacks. © 2013 Elsevier Ltd. All rights reserved.
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O objetivo deste trabalho foi elaborar um produto matinal extrusado de quirera de arroz e bandinha de feijão, além de verificar a influência do processo de extrusão nas suas características físico-químicas, nutricionais, tecnológicas e sensoriais. O produto final apresentou teor considerável de proteínas (9,9 g.100 g-1), podendo ser considerado uma boa fonte desse nutriente para crianças e adolescentes. Para a fibra alimentar, observou-se teor de 3,71 g.100 g-1 do produto pronto para o consumo. Dessa forma, o floco matinal de arroz e feijão pode receber a alegação de alimento fonte de fibras, de acordo com a legislação brasileira. Com relação às propriedades tecnológicas, o extrusado estudado apresentou índice de expansão de 8,89 e densidade aparente de 0,25 g.cm-3. Quanto à análise sensorial, o floco matinal avaliado obteve notas médias de aceitação, situadas no intervalo de 6,8 a 7,7, que corresponde às categorias "gostei ligeiramente" e "gostei muito". Para a intenção de compra, 79% dos provadores opinaram que certamente ou possivelmente comprariam o produto. O emprego de quirera de arroz e bandinha de feijão é uma interessante alternativa para a elaboração de produto matinal extrusado, apresentando boas qualidades de ordem nutricional, tecnológica e sensorial.
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The opportunity to supplement common cassava biscuits with a product of higher nutritional value meets consumer expectations. In this work it was studied the effects of process parameters and flaxseed addition on physical properties of expanded snacks. Extrusion process was carried out using a single screw extruder in a factorial central composite rotatable design with four factors: flaxseed flour percentage (0-20%), moisture (12-20%), extrusion temperature (90-130 °C) and screw speed (190-270). The effect of extrusion variables was investigated in terms of expansion index, specific volume, water absorption index, water solubility index, color parameters (L*, a* ,b*) and hardness. The data analysis showed that variable parameters of the extrusion process and flaxseed flour affected physical properties of puffed snacks. Among the experimental conditions used in the present study, expanded snack products with good physical properties can be obtained under the conditions of 10% flaxseed flour, 230 rpm screw speed, temperature of 90 °C and moisture of 12%.
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Short cooking time and ability to blend varieties of food ingredients have made extrusion cooking a medium for low-cost and nutritionally improved food products. The effect of moisture, extrusion temperature and amount of turmeric flour mixed with cassava flour on physical characteristic of puffed snacks was evaluated in this work. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Results showed effect of extrusion parameters on dependents variables. High expansion, low browning, low water solubility index, intermediate water absorption index and high crispness desirable characteristics to puffed snacks are obtained in conditions of 12% moisture, 5% turmeric flour, 105º C of temperature and 250 rpm of screw speed. These paper point to the potential still unexplored of the use of flours of cassava and turmeric as raw materials in the development of extruded puffed snacks.
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CONTEXTUALIZAÇÃO:O manuseio de materiais está ainda presente nos setores industriais e é associado a lesões na coluna lombar e membros superiores. A inserção de alças em caixas industriais é uma forma de reduzir os riscos relacionados à tarefa, porém a posição e a angulação das alças, que são fatores importantes para o conforto e segurança durante o manuseio, são ainda pouco investigadas objetivamente.OBJETIVOS:Comparar o manuseio de uma caixa comercial e de protótipos com alças e avaliar seus efeitos na postura de membros superiores, atividade elétrica muscular e percepção de agradabilidade em diferentes empunhaduras durante manuseio entre diferentes alturas.MÉTODO:Trinta e sete voluntários saudáveis avaliaram as alças dos protótipos que possibilitavam mudança nas posições (superior e inferior) e angulações (0°, 15° e 30º). Os movimentos dos punhos, cotovelos e ombros foram avaliados por meio da eletrogoniometria e inclinometria. A atividade elétrica muscular dos extensores do punho, bíceps braquial e porção superior do trapézio foi avaliada por um eletromiógrafo portátil. Os registros de movimento e atividade elétrica muscular foram sincronizados. Aspectos subjetivos de agradabilidade foram avaliados por meio de uma escala visual analógica.RESULTADOS E CONCLUSÕES:Os protótipos com alças inclinadas em 30° apresentaram as melhores avaliações de agradabilidade, posturas mais neutras de punho, menores níveis de atividade eletromiográfica do trapézio superior e menores ângulos de elevação dos braços. Os diferentes métodos de medida se mostraram complementares para a avaliação dos membros superiores durante as tarefas de manuseio.
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Leaks in pipes are a common issue encountered in the water industry. Acoustic methods are generally successful in finding and locating leaks in metallic pipes, however, they are less effective when applied to plastic pipes. This is because leak-noise signals are heavily attenuated due to high damping in the pipe-wall and sound radiation into the soil. As result, high frequency leak noise does not travel long distances. To determine how far leak noise may travel in a pipe at any frequency, the attenuation of the wave responsible for leak noise propagation should be known. In this paper a new method to estimate this is described. The method is then applied to some measurements made on a bespoke pipe-test rig in the UK, and the results are compared with theoretical predictions.
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Acoustic techniques have been used for many years to find and locate leaks in buried water distribution systems. Hydrophones and accelerometers are typically used as sensors. Although geophones could be used as well, they are not generally used for leak detection. A simple acoustic model of the pipe and the sensors has been proposed previously by some of the authors of this paper, and their model was used to explain some of the features observed in measurements. However, simultaneous measurements of a leak using all three sensor-types in controlled conditions for plastic pipes has not been reported to-date and hence they have not yet been compared directly. This paper fills that gap in knowledge. A set of measurements was made on a bespoke buried plastic water distribution pipe test rig to validate the previously reported analytical model. There is qualitative agreement between the experimental results and the model predictions in terms of the differing filtering properties of the pipe-sensor systems. A quality measure for the data is also presented, which is the ratio of the bandwidth over which the analysis is carried out divided by the centre frequency of this bandwidth. Based on this metric, the accelerometer was found to be the best sensor to use for the test rig described in this paper. However, for a system in which the distance between the sensors is large or the attenuation factor of the system is high, then it would be advantageous to use hydrophones, even though they are invasive sensors.
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The establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. The aim of this study was to artificially feed partially engorged Dermacentor (Anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. The technique of artificial feeding through plastic tips allowed the engorgement of D. nitens ticks to a final weight within the normal range for the species. (C) 2014 Published by Elsevier GmbH.
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This work has in its outline the analysis of the mechanical properties of the composition of plastic residues, denominated “plastic wood”, aiming at establishing technical parameters for application of this material in substitution to the natural wood. Plastic-Wood is basically, a combination of several kind of plastic, previously selected, washed, dried and without metallic particles, which are agglomerated, extruded or introduced into a mold. The manufacturer can choose different formats and colors. During this monograph it can be observed the use of several kind of plastic, their mechanical properties and the plastic-wood production process. Also are presented features and applications of natural wood, in order to better compare their uses in several applications
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The aim of this in vitro study was to use strain gauge (SG) analysis to compare the effects of the implant-abutment joint, the coping, and the location of load on strain distribution in the bone around implants supporting 3-unit fixed partial prostheses. Three external hexagon (EH) implants and 3 internal hexagon (IH) implants were inserted into 2 polyurethane blocks. Microunit abutments were screwed onto their respective implant groups. Machined cobalt-chromium copings and plastic copings were screwed onto the abutments, which received standard wax patterns. The wax patterns were cast in a cobalt-chromium alloy (n = 5): group 1 = EH/machined. group 2 = EH/plastic, group 3 = IH/machined, and group 4 = IH/plastic. Four SGs were bonded onto the surface of the block tangentially to the implants. Each metallic structure was screwed onto the abutments and an axial load of 30 kg was applied at 5 predetermined points. The magnitude of microstrain on each SG was recorded in units of microstrain (mu epsilon). The data were analyzed using 3-factor repeated measures analysis of variance and a Tukey test (alpha = 0.05). The results showed statistically significant differences for the type of implant-abutment joint, loading point, and interaction at the implant-abutment joint/loading point. The IH connection showed higher microstrain values than the EH connection. It was concluded that the type of coping did not interfere in the magnitude of microstrain, but the implant/abutment joint and axial loading location influenced this magnitude.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The influence of rice, maize, and sorghum raw material particle size in extruded dry dog food on the digestibility of nutrients and energy and the fecal concentration of fermentation products was investigated. Three diets with similar nutrient compositions were formulated, each with 1 starch source. Before incorporation into diets, the cereals were ground into 3 different particle sizes (approximately 300, 450, and 600 mu m); therefore, a total of 9 diets were in a 3 x 3 factorial arrangement (3 cereals and 3 particle sizes). Fifty-four beagle dogs (12.0 +/- 0.1 kg BW) were randomly assigned to the diets, with 6 dogs per diet. The digestibility was measured with the chromium oxide method. The data were evaluated with ANOVA considering the carbohydrate source, grinding effect, and interactions. The means were compared with the Tukey test and polynomial contrasts (P < 0.05). With the same grinding procedure, rice was reduced to smaller particles than other cereals. The cereal mean geometric diameter (MGD) was directly related to starch gelatini-zation (SG) during extrusion. For rice diets, the MGD and SG did not change nutrient digestibility (P > 0.05); only GE digestibility was reduced at the largest MGD (P < 0.01). For maize and sorghum diets, the total tract apparent nutrient digestibility was reduced for foods with greater MGD and less SG (P < 0.01). A linear reduction in nutrient digestibility according to cereal particle size was observed for sorghum (r(2) < 0.72; P < 0.01). Higher concentrations of fecal total shortchain fatty acids (SCFA) were observed for sorghum diets (P < 0.05) than for other diets. The rice diets led to the production of feces with less lactate (P < 0.05). The increase in raw material MGD did not influence fecal SCFA for rice diets, but for the dogs fed maize and sorghum foods, an increase in propionate and butyrate concentrations were observed as MGD increased (P < 0.05). In conclusion, for dogs fed different particle sizes of the cereal starches in the extruded diets, the digestibility and fecal characteristics were affected, and this effect was ingredient dependent.