Activity of Delta(9)-desaturase enzyme in mammary gland of lactating buffaloes

The objective of this research was to measure the activity of e-desaturase enzyme in lactating buffaloes. Data from forty lactating Murrah-crossbred buffaloes were collected on five commercial farms located at Sarapui and Pilar do Sul, São Paulo-Brazil. A field survey was done from April to November 2002. In four farms, buffaloes were fed with wet brewers grains (primary concentrate). Only one farm (Farm 4) offered pasture and corn silage. Monthly milk samples were collected and stored at -20 degrees C until analyzed for fatty acid composition. The Delta(9)-desaturase activity was measured using an indirect method (myristoleic and myristic acids ration - C(14:1c9)/C(14:0)). The higher C(14:1c9)/C(14:0) rate was verified on Farm 4 (0.092). The C(14:1c9)/C(14:0) ratio were 0.064 to Farm 1; 0.065 to Farm 2; 0.062 to Farm 3 and 0.065 to Farm 5. The C(17:1)/C(17:0), C(18:1c9)/C(18:0) and C(18:2c9t11)/C(18:1t11) ratios were also affected. The Farm 4 showed higher value for all ratios. Therefore, in lactating buffaloes grazing pasture the Delta(9)-desaturase activity could be enhanced.

Oxygen stoichiometry effects in spinel-type NiMn2O4-delta samples

We report the effects of oxygen stoichiometry in the structure and magnetic response of spinel-type NiMn2O4-delta polycrystalline samples controlled by heat-treatments in different atmospheric conditions.The post-annealed samples were analyzed by Scanning Electron Microscopy associated to X-ray Energy Dispersion Spectrometry, X-ray Photoelectron Spectroscopy and AC/DC magnetic measurements.Results indicate that the oxygen stoichiometry highly influences the magnetic interactions between the ferromagnetic, and antiferromagnetic sublattices in these compounds due to the presence of manganese in three possible valence states. (c) 2005 Elsevier Ltd. All rights reserved.

Generalization of the delta-differential autotransformer for 12 and 18-pulse converters

This work proposes a methodology to generalize the A-connections for 12 and 18-pulse autotransformers. A single mathematical expression, obtained through simple trigonometric operations, represents all the connections. The proposed methodology allows choosing any ratio between the input and the output voltages. The converters can operate either as step-up or as step-down voltage. To simplify the design of the windings, graphics are generated to calculate the turn-ratio and the polarity of each secondary winding, with respect to the primary winding. A design example, followed by digital simulations, and experimental results illustrate the presented steps. The results also show that high power factor is an inherent characteristic of multi-pulse converters, without any active or passive power factor pre-regulators needs.

Acoustic measurement of the low-energy excitations in Nd2-xCexCuO4+delta

The complex dynamic Young's modulus of ceramic Nd2-xCexCuO4 with x = 0, 0.05 and 0.20 has been measured from 1.5 to 100 K at frequencies of 1 - 10 kHz. In the undoped sample the modulus starts decreasing below similar to 20 K, instead of approaching a constant value as in a normal solid. The modulus minimum has been interpreted in terms of paraelastic contribution from the relaxation of the Nd3+ 4f electrons between the levels of the ground state doublet, which is split by the interaction with the antiferromagnetically ordered Cu sublattice. The value of the splitting is found to be 0.34 meV, in excellent agreement with inelastic neutron scattering, infrared and specific heat experiments. With doping, the anomaly shifts to lower temperature and decreases in amplitude, consistently with a reduction of the local field from the Cu sublattice. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Room temperature co-precipitation of nanocrystalline CeO2 and Ce0.8Gd0.2O1.9-delta powder

This paper describes a simple method to co-precipitate CeO2 and Ce0.8Gd0.2O1.9-delta with ammonium hydroxide from solvents such as: water, ethylene glycol, ethyl alcohol and isopropyl alcohol. Characterization by Raman spectroscopy and XRD evidenced the formation of a solid solution of gadolinium-doped ceria at room temperature. Nanometric particles with crystallite size of 3.1 nm were obtained during synthesis using ethyl alcohol as solvent. This is a promising result compared with those mentioned in the literature, in which the smallest crystallite size reported was, 6.5 nm. (c) 2006 Elsevier B.V. All rights reserved.

Microstructural and transport properties of LaNiO3-delta films grown on Si(111) by chemical solution deposition

Electrically conductive LaNiO3-delta (LNO) thin films with typical thickness of 200 nm were deposited on Si (111) substrates by a chemical solution deposition method and heat-treated in air at 700 degreesC. Structural, morphological, and electrical properties of the LNO thin films were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), field-emission scanning electron microscopy (FEG-SEM), and electrical resistivity rho(T). The thin films have a very flat surface and no droplet was found on their surfaces. The average grain size observed by AFM and FEG-SEM was approximately 100 nm in excellent agreement with XRD data. The rho(T) data showed that these thin films display a good metallic character in a large range of temperature. These results suggest the use of this conductive layer as electrode in the integration of microelectronic devices. (C) 2003 Elsevier B.V. All rights reserved.

Structure, mobility and clustering of interstitial O in La2CuO4+delta in the limit of small delta

Anelastic spectra (elastic energy absorption as a function of temperature) are reported which provide evidence that excess O in La2CuO4+delta starts forming two different types of defects already at very low concentrations, where no phase separation or changes in the type of O intercalation are believed to occur. The absorption peak with the lowest activation enthalpy, H/k(B) = 5600 K, is visible at lowest values of delta and is attributed to the hopping of single interstitial O2- ions. The second process, with a slightly slower dynamics, appears at higher values of delta and soon becomes preponderant over the former process. The latter process is proposed to be due to stable pairs of O atoms and is put in connection with the formation of partially covalent bonds between interstitial and apical oxygen; such bonds would reduce the doping efficiency of excess O at increasing delta. The geometry of the interstitial O defect is discussed. O 1998 Published by Elsevier B.V. B.V. All rights reserved.

Efeito do período de jejum na fase final de crição de frangos de corte machos sobre rendimento e composição da carcaça

The objective of this work was to evaluate the effect of fasting period in the last growing phase on carcass yield and composition of male broilers. Two thousand one-day old male chicks were distributed in five randomized blocks according to a 4x2 factorial (four feeding programs (P): ad libitum or one of three fasting schedules: 8-12, 12-16 and 8-16; and two strains (S): Ross or Hubbard-Peterson, Fifty birds were used per replicate. Birds were raised under identical feed and management conditions until day 42. The fasting schedules were applied from day 43 to day 56. At day 56, five birds per replicate were randomly sampled, weighed, slaughtered, eviscerated, dry-cooled, cut and deboned. No effects of P or SxP interaction were observed for carcass characteristics. birds, which showed higher weights and yields of head plus neck, feet, leg bones and wings. The ad libitum birds showed higher crude protein in thigh meat than those submitted to the 8-12 h fast. A SxP interaction was observed for meat ash content. The R broilers showed higher ash content in breast and thigh meat than the H birds in the 8-12 h fast treatment. on the other hand, the R broilers submitted to the 8-12 h fast showed higher ash contents in breast and thigh meat than birds from the same strain in the other feeding programs. Fasting in the last phase of rearing did not alter the yield of whole carcass, carcass cuts and abdominal fat, but morning fast influenced carcass chemical composition.

Oxygen mobility in SmBa2Cu3O7-delta measured by anelastic spectroscopy

Anelastic spectroscopy has been performed on a sample of superconducting oxide SmBa2Cu3O7-delta (SBCO) using a torsion pendulum operating with frequency around 10 Hz. A thermally activated relaxation peak is observed near 500 K with the activation enthalpy of 1.55 +/- 0.03 eV and the pre-exponential factor of approximately 10(-15) s, which is attributed to the mobility of non-stoichiometric oxygen by jumps in positions O1 and O5 of the lattice. (c) 2006 Elsevier B.V. All rights reserved.

Adubação potássica da soja em latossolo vermelho-escuro fase arenosa

Durante três anos foi conduzido um experimento em Latossolo Vermelho-Escuro fase arenosa, no qual foram estudados os efeitos de adubações anuais com 0,40, 80, 160 e 240 kg/ha de K2O, nas formas de cloreto de potássio e sulfato de potássio, aplicados no sulco de semeadura ou em área total com incorporação. Observou-se resposta à adubação potássica a partir do segundo ano de cultivo. As máximas produções sempre estiveram associadas a teores de potássio nas folhas acima de 1,5%. Em anos mais secos que o normal, as aplicações a lanço proporcionaram melhores resultados do que as aplicações em sulcos. Não foram observadas diferenças entre as fontes de potássio utilizadas. Notou-se acentuado decréscimo nos teores de potássio trocável do solo, com o transcorrer do tempo, sendo necessária a aplicação de doses maiores que 80 kg/ha de K2O por ano para manter o nível original. Por outro lado, a aplicação de doses elevadas de potássio levou a uma perda significativa do nutriente por lixiviação.

Efeito do tipo de dieta e do sistema de alimentação na fase inicial sobre o desempenho de leitões

In this experiment, 96 piglets (Large White x Landrace) were fed simple (SD) or semi-complex (SCD) diets during the initial phase (SP), using a controlled (C) or ad libitum (AL) schedules during the first 14 days of the SP and ad libitum for the rest of SP. By the end of SP one male and one female from each pen were transferred to growing finishing pens where they were fed ad libitum diets specific to each phase. The experimental design consisted of randomized complete blocks with six replicates by treatment. Higher average daily feed intakes (ADFI) were observed during the first 14 days of the SP by pigs fed SCD. Pigs fed AL showed higher ADFI and average daily gains (ADG). No treatment differences were observed between the treatments in feed conversion (FC) or in incidence and severity of diarrhea. Considering SP as a whole, there was no effect of treatments on the variables studied. Treatments used in SF did not affect ADFI and ADG during the growing-finishing phases (GFP), although pigs fed SD showed better FC. The ADG was nor affected by treatments when the total period (SP+GFP) was considered. It can be concluded that a similar performance was obtained when SD or SCD were feci during the initial phase. independently of the feeding system.

Estudo experimental sobre a intoxicação de Gallus gallus domesticus com semente de crotalaria spectabilis. II efeito em aves na fase final de crescimento

This study was undertaken to investigate the toxic effect of Crotalaria spectabilis seeds added to the ration for commercial broilers during the final phase of growth. Ground seeds were added at different concentrations to the ration: 0.0% (control), 0.01%, 0.1% and 0.4%. Rations containing 0.4% caused symptoms of intoxication, beginning in the second week of the study. During the third week birds showed bristling, apathy, general weakness, distended abdomen and agglomeration. In the fourth week, four animals died. Necropsy revealed prominent ascites and severe lesions of liver, kidney and lung. Microscopic examination revealed necrosis of hepatocytes, inflammatory cell infiltration, hypertrophy and hyperplasia of biliary duct cells leading to atresia and cholestasis. Prominent cartilaginous and osseous nodules in the lungs were also present as well as degenerative, changes in the kidney tubules and necrosis of cells of the bursa. All the broilers receiving a ration with 0.1% of Crotalaria seeds showed ascites and slight lesions of the liver. The remaining groups showed no reduction in weight gains, lesions or clinical symptoms. It is concluded that broilers during the final phase of growth are sensitive to administrations of seeds of C. spectabilis in their ration. The presence of ascites and cartilaginous and osseous nodules in the lungs of the affected birds was also considered important.

Farelo de trigo e complexo enzimático na alimentação de poedeiras semipesadas na fase de produção

The study was carried out with the objective to evaluate the effects of the inclusion of the wheat bran (WB) with or without supplementation of an enzymatic complex (EC) on the performance of semi-heavy hens in the egg-production phase. A total of 288 Lohmann Brown pullets were used, distributed to a completely randomized design in 4 x 2 factorial arrangement, composed by four WB levels (0, 3, 6 and 9%) in the ration and enzymatic complex supplementation (0 or 100g/100 kg diet), with eight treatments and six replicates of six birds. The enzymatic complex contained the enzymes beta-galactosidase, galactomananase, xilanase and alpha-glucanase. Feed intake, final body weight, egg production, egg weight, egg mass, egg mass feed conversion or egg dozen feed conversion was not affected by WB inclusion in the diets. Egg shell specific gravity deteriorated as WB levels increase in the diets. None of the characteristics was affected by the enzymatic complex supplementation, except for egg weight, that improved from 62.74 to 64.28 g. Then, the use up to 9.0% of wheat bran in the ration is recommended for semi-heavily chickens in the production phase. The supplementation of alpha-galactosidase, galactomannanase, xylanase and alpha-glucanase improve egg weight.

A Family of Autoconnected Transformers for 12-and 18-Pulse Converters-Generalization for Delta and Wye Topologies

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