11 resultados para Vehicle bodies.

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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To obtain a probiotic caprine Coalho cheese naturally enriched in conjugated linoleic acid (CLA), goats' diet was supplemented with soybean oil to produce CLA-enhanced milk, and Lactobacillus acidophilus La5 was incorporated into cheeses. CLA concentration and probiotic viability were evaluated during 60 days. Four pilot-scale cheese-making trials were manufactured, in triplicates. Cheeses T1 and T2 were produced with control milk, and T3 and T4 with CLA-enhanced milk. L. acidophilus was added to cheeses T2 and T4 during processing. The CLA content (isomer C18:2 cis-9, trans-11) in T3 and T4 was 246% to 291% higher than in T1 and T2 (P < 0.01). Populations of L. acidophilus were around 7.5 log cfu g(-1) in T2 and T4 during the study, and the highest CLA content in T4 did not influence the probiotic viability (P > 0.01). The CLA-enriched probiotic caprine Coalho cheese obtained is proposed as a vehicle for beneficial microorganisms and fatty acids. (C) 2012 Elsevier Ltd. All rights reserved.

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The determination of hydrodynamic coefficients of full scale underwater vehicles using system identification (SI) is an extremely powerful technique. The procedure is based on experimental runs and on the analysis of on-board sensors and thrusters signals. The technique is cost effective and it has high repeatability; however, for open-frame underwater vehicles, it lacks accuracy due to the sensors' noise and the poor modeling of thruster-hull and thruster-thruster interaction effects. In this work, forced oscillation tests were undertaken with a full scale open-frame underwater vehicle. These conducted tests are unique in the sense that there are not many examples in the literature taking advantage of a PMM installation for testing a prototype and; consequently, allowing the comparison between the experimental results and the ones estimated by parameter identification. The Morison's equation inertia and drag coefficients were estimated with two parameter identification methods, that is, the weighted and the ordinary least-squares procedures. It was verified that the in-line force estimated from Morison's equation agrees well with the measured one except in the region around the motion inversion points. On the other hand, the error analysis showed that the ordinary least-squares provided better accuracy and, therefore, was used to evaluate the ratio between inertia and drag forces for a range of Keulegan-Carpenter and Reynolds numbers. It was concluded that, although both experimental and estimation techniques proved to be powerful tools for evaluation of an open-frame underwater vehicle's hydrodynamic coefficients, the research provided a rich amount of reference data for comparison with reduced models as well as for dynamic motion simulation of ROVs. [DOI: 10.1115/1.4004952]

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Despite the efficacy of topical retinoic acid, skin reactions have limited its acceptance by patients. Other retinoids, like Retinyl Palmitate (RP), are considerably less irritating, but they are also less effective. In order to enhance the performance of retinoids, in this work RP has been added to cosmetic formulations such as nanoemulsions, which can provide better penetration of this active substance. Because the vehicle can directly influence the skin penetration and the effectiveness of RP, two skin care products containing 5000 UI RP have been developed and investigated, namely a nanoemulsifying system and a classic gel cream. In vitro penetration tests were conducted by using Franz diffusion cells and placing porcine ear skin and iso-propanol in the receptor compartment. The RP concentration in the skin layers was analyzed by high performance liquid chromatography, and a Zeta-Sizer system was employed for measurement of the the particle size distribution. The penetration tests revealed a large difference between the vehicles in terms of the RP concentrations in each skin layer. The classic gel cream furnished better RP penetration in both the stratum corneum and the epidermis without stratum corneum + dermis, as compared to the self-nanoemulsifying system. The two vehicles displayed the same particle size (between 100 and 200 nm). Better understanding of RP skin delivery using different vehicles has been acquired, and the importance of evaluating the efficacy of nanocosmetics. Results from the present study should also contribute to the assessment of commercial self-nanoemulsifying systems with potential application in the facile production of nanoemulsions.

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A semi-autonomous unmanned underwater vehicle (UUV), named LAURS, is being developed at the Laboratory of Sensors and Actuators at the University of Sao Paulo. The vehicle has been designed to provide inspection and intervention capabilities in specific missions of deep water oil fields. In this work, a method of modeling and identification of yaw motion dynamic system model of an open-frame underwater vehicle is presented. Using an on-board low cost magnetic compass sensor the method is based on the utilization of an uncoupled 1-DOF (degree of freedom) dynamic system equation and the application of the integral method which is the classical least squares algorithm applied to the integral form of the dynamic system equations. Experimental trials with the actual vehicle have been performed in a test tank and diving pool. During these experiments, thrusters responsible for yaw motion are driven by sinusoidal voltage signal profiles. An assessment of the feasibility of the method reveals that estimated dynamic system models are more reliable when considering slow and small sinusoidal voltage signal profiles, i.e. with larger periods and with relatively small amplitude and offset.

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Preformed structural reinforcements have shown good performance in crash tests, where the great advantage is their weight. These reinforcements are designed with the aim of increasing the rigidity of regions with large deformations, thus stabilising sections of the vehicle that work as load path during impact. The objective of this work is to show the application of structural reinforcements made of polymeric material PA66 in the field of vehicle safety, through finite element simulations. Simulations of frontal impact at 50 km/h and in ODB (offset deformable barrier) at 57 km/h configurations (standards such as ECE R-94 and ECE R-12) were performed in the software LS-DYNA R (R) and MADYMO (R). The simulations showed that the use of polymeric reinforcements leads to a 70% reduction in A-pillar intrusion, a 65% reduction in the displacement of the steering column and a 59% reduction in the deformation in the region of the occupant legs and feet. The level of occupant injuries was analysed by MADYMO (R) software, and a reduction of 23.5% in the chest compression and 80% in the tibia compression were verified. According to the standard, such conditions lead to an improvement in the occupant safety in a vehicle collision event.

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In Brazil, the principal source of air pollution is the combustion of fuels (ethanol, gasohol, and diesel). In this study, we quantify the contributions that vehicle emissions make to the urban fine particulate matter (PM2.5) mass in six state capitals in Brazil, collecting data for use in a larger project evaluating the impact of air pollution on human health. From winter 2007 to winter 2008, we collected 24-h PM2.5 samples, employing gravimetry to determine PM2.5 mass concentrations; reflectance to quantify black carbon concentrations; X-ray fluorescence to characterize elemental composition; and ion chromatography to determine the composition and concentrations of anions and cations. Mean PM2.5 concentrations in the cities of Sao Paulo, Rio de Janeiro, Belo Horizonte, Curitiba, Porto Alegre, and Recife were 28, 17.2, 14.7, 14.4, 13.4, and 7.3 mu g/m(3), respectively. In Sao Paulo and Rio de Janeiro, black carbon explained approximately 30% of the PM2.5 mass. We used receptor models to identify distinct source-related PM2.5 fractions and correlate those fractions with daily mortality rates. Using specific rotation factor analysis, we identified the following principal contributing factors: soil and crustal material; vehicle emissions and biomass burning (black carbon factor); and fuel oil combustion in industries (sulfur factor). In all six cities, vehicle emissions explained at least 40% of the PM2.5 mass. Elemental composition determination with receptor modeling proved an adequate strategy to identify air pollution sources and to evaluate their short- and long-term effects on human health. Our data could inform decisions regarding environmental policies vis-a-vis health care costs.

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Abstract (2,250 Maximum Characters): Several theories of tidal evolution, since the theory developed by Darwin in the XIX century, are based on the figure of equilibrium of the tidally deformed body. Frequently the adopted figure is a Jeans prolate spheroid. In some case, however, the rotation is important and Roche ellipsoids are used. The main limitations of these models are (a) they refer to homogeneous bodies; (b) the rotation axis is perpendicular to the plane of the orbit. This communication aims at presenting several results in which these hypotheses are not done. In what concerns the non-homogeneity, the presented results concerns initially bodies formed by N homogeneous layers and we study the non sphericity of each layer and relate them to the density distribution. The result is similar to the Clairaut figure of equilibrium, often used in planetary sciences, but taking into full account the tidal deformation. The case of the rotation axis non perpendicular to the orbital plane is much more complex and the study has been restricted for the moment to the case of homogeneous bodies.

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BACKGROUND: Evaluations of clinical depression are traditionally based on verbal information. Nonverbal expressive behavior, however, being associated with a person's reflexive responses, may reveal negative emotional or social processes that are not under complete control of the patients. However, investigations of nonverbal behavior in the evaluation of depressed patients are still scarce. This study examines the nonverbal behaviors of a group of Brazilian patients, associating their nonverbal behavior with severity of depression. METHODS: Forty depressed patients were evaluated at baseline (T0) and after a two-week transcranial direct current stimulation treatment (T1), according to rating scales and through a 21-category Ethogram for assessment of the frequency of nonverbal behaviors displayed during an interview. RESULTS: Behaviors that were related to negative feelings and social disinterest decreased with corresponding clinical improvement and were associated with increased severity of symptoms at T0 and greater negative affect and dissatisfaction at T1. Pro-social behaviors were associated with milder symptoms at T0 and increased after treatment. Facial, head and hand expressive movements stood out as important indicators because of their associations with severity of depression. LIMITATIONS: Duration of behaviors was not assessed and there was not a healthy control group with which to compare the findings. CONCLUSIONS: These results support the usefulness of nonverbal behavior as an evaluation technique in the assessment of clinical depression.

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This study addresses a vehicle routing problem with time windows, accessibility restrictions on customers, and a fleet that is heterogeneous with regard to capacity and average speed. A vehicle can performmultiple routes per day, all starting and ending at a single depot, and it is assigned to a single driverwhose totalwork hours are limited.Acolumn generation algorithmis proposed.The column generation pricing subproblem requires a specific elementary shortest path problem with resource constraints algorithm to address the possibility for each vehicle performingmultiple routes per day and to address the need to set the workday’s start time within the planning horizon. A constructive heuristic and a metaheuristic based on tabu search are also developed to find good solutions.

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Histological and ultrastructural analyses of gills were observed in Nile tilapia collected from three different waterbodies in southeast Brazil: an urban lake in a park in the city of São Paulo, a reservoir in a rural city, and a commercial aquaculture facility. These aterbodies were analyzed and classified as hypereutrophic, eutrophic, and supereutrophic, respectively, with 310.00, 94.00, 28.00 of phosphate (PO2_ 4 lg L _1) and 65.49, 24.95, 12.83 of chlorophyll (lg L _1). A significant difference in the histological alterations index (HAI) was observed only in fish from the urban lake, with the presence of cell hypertrophy, hyperplasia, aneurism, and other alterations. When compared to the other groups, a large quantity of rodlet cells was also observed in the urban group. These results demonstrate the correlation of eutrophic states of water with gill morphology. Also discussed is the premise that large amounts of organic material dissolved in water can alter the morphology of the fish gills