857 resultados para Alternative Formulations


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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O equino é um herbívoro não ruminante capaz de suprir grande parte ou a totalidade da sua demanda nutricional pela ingestão de gramíneas. Apresenta a região ceco-cólica bastante desenvolvida, sendo este o principal sítio de fermentação. Este processo também ocorre na região aglandular do estômago, porém a produção de ácidos graxos voláteis é inferior, quando comparado ao intestino grosso. O conhecimento do sítio de aproveitamento de cada ingrediente é de suma importância para a combinação dos mesmos, favorecendo o ótimo aproveitamento de cada um deles e evitando excessos que podem ser prejudiciais ao metabolismo do equino. O estudo atual do fracionamento de carboidratos, por mais que não seja adaptado a fisiologia e metabolismo dos equinos, nos fornece informações sobre as diferentes frações que o compõem e com isso pode-se inferir sobre a produção de energia por cada fração gerada. A manutenção de equinos em pastejo ou sob o fornecimento de feno ou alimentos volumosos é essencial para a manutenção da atividade e saúde do seu trato digestório. O aporte mínimo de 12% de FDN garante tal situação. Atualmente, com o objetivo de aumentar a disponibilidade de energia, ingredientes como a polpa cítrica, polpa de beterraba e casca de soja, vem sendo utilizados nas formulações. Estes ingredientes de fermentação mais rápida e fácil, são uma alternativa segura para elevar a concentração energética da dieta de equinos, por proporcionar a diminuição do aporte de amido na dieta de equinos. Sabe-se entretanto, que com a elevação na qualidade do volumoso, maiores concentrações de carboidratos solúveis e de rápida fermentação são encontrados disponíveis ao longo do trato digestório dos equinos levando a alguns distúrbios metabólicos como a laminite e a sensibilidade a insulina. Com o correto manejo dos animais em pastejo e conhecimento do ciclo da planta é possível minimizar tais problemas. Objetivou-se revisão da ação fisiológica e metabólica das diferentes frações fibrosas, em cada compartimento do trato digestório, bem como destacar os ingredientes volumosos com suas diversas frações, os quais possibilitam sugerir manejo alimentar adequado para os equinos.

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The dynamics of the restricted three-body Earth-Moon-particle problem predicts the existence of direct periodic orbits around the Lagrangian equilibrium point L1. From these orbits, we derive a set of trajectories that form links between the Earth and the Moon and are capable of performing transfers between terrestrial and lunar orbits, in addition to defining an escape route from the Earth-Moon system. When we consider a more complex and realistic dynamical system - the four-body Sun-Earth-Moon-particle (probe) problem - the trajectories have an expressive gain of inclination when they penetrate in the lunar influence sphere, thus allowing the insertion of probes into low-altitude lunar orbits with high inclinations, including polar orbits. In this study, we present these links and investigate some possibilities for performing an Earth-Moon transfer based on these trajectories. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

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This paper describes 2 alternative methodologies for the determination of selected aldehydes (formaldehyde, acetaldehyde, propionaldehyde, acrolein, and benzaldehyde) by capillary electrophoresis (CE), the first approach is based on the formation of aldehyde-bisulfite adducts and employs free solution CE with reversed electroosmotic flow and indirect detection, using 10 mmol/L 3,5-dinitrobenzoic acid (pH 4.5) containing 0.2 mmol/L cetyltrimethylammonium bromide as the electrolyte. This novel methodology showed a fairly good sensitivity to concentration, with detection limits with respect to a single aldehyde on the order of 10-40 mu g/L, a reasonable analysis time (separation was achieved in <8 min), and no need for sample manipulation. A second approach was proposed in which 2,4-dinitrophenylhydrazine derivatives of the aldehydes were detected in a micellar electrolyte medium (20 mmol/L berate buffer containing 50 mmol/L sodium dodecyl sulfate and 15 mmol/L beta-cyclodextrin). This latter methodology included a laborious sample preconcentration step and showed much poorer sensitivity (0.5-2 mg/L detection limit, with respect to a single aldehyde), despite the use of sodium chloride to promote sample stacking. Both methodologies proved adequate to evaluate aldehyde levels in vehicular emissions. Samples from the tailpipe exhaust of a passenger car vehicle without a catalytic converter and operated with an ethanol-based fuel were collected and analyzed; the results showed high levels of formaldehyde and acetaldehyde (0.41-6.1 ppm, v/v). The concentrations estimated by the 2 methodologies, which were not in good agreement, suggest the possibility of striking differences in sample collection efficiency, which was not the concern of this work.

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Purpose - This paper proposes an interpolating approach of the element-free Galerkin method (EFGM) coupled with a modified truncation scheme for solving Poisson's boundary value problems in domains involving material non-homogeneities. The suitability and efficiency of the proposed implementation are evaluated for a given set of test cases of electrostatic field in domains involving different material interfaces.Design/methodology/approach - the authors combined an interpolating approximation with a modified domain truncation scheme, which avoids additional techniques for enforcing the Dirichlet boundary conditions and for dealing with material interfaces usually employed in meshfree formulations.Findings - the local electric potential and field distributions were correctly described as well as the global quantities like the total potency and resistance. Since, the treatment of the material interfaces becomes practically the same for both the finite element method (FEM) and the proposed EFGM, FEM-oriented programs can, thus, be easily extended to provide EFGM approximations.Research limitations/implications - the robustness of the proposed formulation became evident from the error analyses of the local and global variables, including in the case of high-material discontinuity.Practical implications - the proposed approach has shown to be as robust as linear FEM. Thus, it becomes an attractive alternative, also because it avoids the use of additional techniques to deal with boundary/interface conditions commonly employed in meshfree formulations.Originality/value - This paper reintroduces the domain truncation in the EFGM context, but by using a set of interpolating shape functions the authors avoided the use of Lagrange multipliers as well Mathematics in Engineering high-material discontinuity.

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A flow-injection spectrophotometric procedure is proposed for methyldopa determination in pharmaceutical preparations. The determination is based on formation of a yellow product (measured at 410 nm) after complexation of methyldopa with molybdate. Under optimal conditions, Beer's law is obeyed in a concentration range of 50-200 mg l(-1) methyldopa. Typical correlation between absorbance and analyte concentration was 0.9999. Usual excipients used as additives in pharmaceuticals do not interfere with the proposed method. The analytical frequency was 210 h(-1) and the relative standard deviation (R.S.D.) was <= 2% for sample solution containing 150 mg l(-1) methyldopa (n = 11). The analytical results obtained in commercial formulations by applying the proposed FIA method were in good agreement with labeled values and those obtained by the Brazilian Pharmacopoeia procedure at 95% confidence level. (C) 2005 Elsevier B.V. All rights reserved.

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We present a non-radioactive alternative to Southern's (J. Mol. Biol. 98: 503-517, 1975) DNA-DNA hybridization technique. The use of AMPPD - Disodium 3-(4-Methoxyspiro {1,2-dioxetane-3,2'tricyclo[3.3.1.1(3,7)]decan}-4-yl)phyenyl phosphate as an alternative substrate for AP-mediated detection of digoxigenin-11 dUTP-labeled probes made possible the simple and nonhazardous reuse of blots. We used 0.8 % agarose gels containing 30 mug per lane of Eucalyptus saligna DNA, digested with Eco RI, electrophoresed and blotted on to nylon membranes (Hybond-N, Amersham, UK), using the Southern blotting procedure, and UV irradiated for one minute for DNA fixation. The hybridizations were carried out overnight with digoxigenin labeled random inserts of E. saligna DNA by using the Genius Kit (Boehringer Mannheim). Detection of the DNA-DNA hybrids was performed in the presence of 0.5% blocking agent and the substrates NBT/BCIP were replaced by 0.26 mM AMPPD in the final alkaline assay buffer (50 mul/cm2). After membrane incubation for five minutes at room temperature in a sealed plastic bag, the AMPPD solution was retrieved and stored at 4-degrees-C for reuse. A Kodak X-BRAF QA-S film was pressed firmly onto the bag containing the wet membrane, exposed for two to six hours and then developed. After use, the probes were stripped off and the blots reutilized, three times so far, with the same results.

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The production of antimicrobial compounds of some strains of Lactobacillus acidophilus has been studied. They have been grown in whey supplemented with soy milk. It has been found that the production of compounds is able to inhibit the growing of both target bacteria analysed: Staphylococcus aureus and Escherichia coli. The results showed a significant variation (p>0.05) depending on the strain of L. acidophilus and on the level of supplementation utilized. Most of the inhibition observed resulted from the presence of the lactic acid produced. It has also been found the production of other antimicrobial compounds showing inhibitory capacity. The action of these compounds was influenced by the substract pH.

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The conventional power flow method is considered to be inadequate to obtain the maximum loading point because of the singularity of Jacobian matrix. Continuation methods are efficient tools for solving this kind of problem since different parameterization schemes can be used to avoid such ill-conditioning problems. This paper presents the details of new schemes for the parameterization step of the continuation power flow method. The new parameterization options are based on physical parameters, namely, the total power losses (real and reactive), the power at the slack bus (real or reactive), the reactive power at generation buses, and transmission line power losses (real and reactive). The simulation results obtained with the new approach for the IEEE test systems (14, 30, 57, and 118 buses) are presented and discussed in the companion paper. The results show that the characteristics of the conventional method are not only preserved but also improved.

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New parameterization schemes have been proposed by the authors in Part I of this paper. In this part these new options for the parameterization of power flow equations are tested, namely, the total power losses (real and reactive), the power at the slack bus (real or reactive), the reactive power at generation buses, and the transmission line power losses (real and reactive). These different parameterization schemes can be used to obtain the maximum loading point without ill-conditioning problems, once the singularity of Jacobian matrix is avoided. The results obtained with the new approach for the IEEE test systems (14, 30, 57, and 118 buses) show that the characteristics of the conventional method are not only preserved but also improved. In addition, it is shown that the proposed method and the conventional one can be switched during the tracing of PV curves to determine, with few iterations, all points of the PV curve. Several tests were also carried out to compare the performance of the proposed parameterization schemes for the continuation power flow method with the use of both the secant and tangent predictors.

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The characteristics, performance, and application of an electrode, namely, Pt\Hg\Hg-2(PABzt)(2)\ graphite, where PABzt stands for p-aminobenzoate ion, are described. This electrode responds to PABzt with sensivity of (58.1 +/- 1.0) mV per decade over the range 1.0 x 10(-4) to 1.0 x 10(-1) mol l(-1) at pH 6.5-8.0 and a detection limit of 3.2 x 10(-5) mol l(-1). The electrode shows easy construction, fast response time (within 10-30 s), low-cost, and excellent response stability (lifetime greater than 6 months, in continuous use). The proposed sensor displayed good selectivity for p-aminobenzoate in the presence of several substances, especially, concerning carboxylate and inorganic anions. It was used to determine p-aminobenzoate in pharmaceutical formulations by means of the standard additions method. The results obtained by using this electrode compared very favorably with those given by an HPLC procedure. (C) 2004 Elsevier B.V. All rights reserved.

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Statement of problem. The success of metal-ceramic restorations is influenced by the compatibility between base metal alloys and porcelains. Although porcelain manufacturers recommend their own metal systems as the most compatible for fabricating metal-ceramic prostheses, a number of alloys have been used.Purpose. This study evaluated the shear bond strength between a porcelain system and 4 alternative alloys.Material and methods. Two Ni-Cr alloys: 4 ALL and Wiron 99, and 2 Co-Cr alloys: IPS d.SIGN 20 and Argeloy NP were selected for this study. The porcelain (IPS d.Sign porcelain system) portion of the cylindrical inetal-ceramic specimens was 4 mm thick and 4 mm high; the metal portion was machined to 4 x 4 mm, with a base that was 5 nun thick and 1 mm high. Forty-four specimens were prepared (n=11). Ten specimens from each group were subjected to a shear load oil a universal testing machine using a 1 min/min crosshead speed. One specimen from each group was observed with a scanning electron microscope. Stress at failure (MPa) was determined. The data were analyzed with a 1-way analysis of variance (alpha=.05).Results. The groups, all including IPS d.Sign porcelain, presented the following mean bond strengths (+/-SD) in MPa: 4 ALL, 54.0 +/- 20.0; Wiron, 63.0 +/- 13.5; IPS d.SIGN 20, 71.7 +/- 19.2; Argeloy NP, 55.2 +/- 13.5. No significant differences were found among the shear bond strength values for the metal-ceramic specimens tested.Conclusion. None of the base metal alloys studied demonstrated superior bond strength to the porcelain tested.

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In this report an analytical method to determine furosemide by using diffuse reflectance spectroscopy is presented. This study shows that this technique can give quantitative results using spot test analysis, particularly in the case of pharmaceuticals containing furosemide. The color spot test could be obtained by reaction between furosemide with p-dimethylaminocinnamaldehyde, in acid medium. This reaction produced a stable complex on filter paper after heating to 80degreesC for 5 min. All reflectance measurements were carried out at 585 nm and the linear range was from 7.56 x 10(-3) to 6.05 x 10(-2) mol l(-1), with a correlation coefficient of 0.999. The limit of detection was estimated to be 2.49 x 10(-3) mol l(-1) (R.S.D. = 1.7%) and the effect of common excipients on the reflectance measurements was evaluated. The method was applied to determine furosemide in commercial brands of pharmaceuticals. The results obtained by the proposed method were favorably compared with those of the official method, showing for the first time ever that quantitative spot test analysis by diffuse reflectance could be successfully used to determine furosemide in tablets. (C) 2004 Elsevier B.V. All rights reserved.

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A sensitive method is described for the determination of cefaclor by cathodic stripping voltammetry at the hanging mercury drop electrode. cefaclor is accumulated at the electrode surface as a mercury salt, which is reduced at -0.67 V. The optimum accumulation potential and accumulation time were +0.15 V and up to 180 s, respectively. Linear calibration graphs were obtained between 3.9 mu g.L-1 to 39 mu g.L-1 and the limit of determination was evaluated to be 1.9 mu g.L-1. The method was applied successfully to the determination of cefaclor in pharmaceutical formulations.