273 resultados para Roughage: concentrate ratio
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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This research aimed at evaluating the effect of the semiarid climatic conditions on the physiological behavior of F1 Saanen x Boer crossbred goats, created at an intensive system. The experiment was carried out in the Health and Rural Technology Center, in the Federal University of Campina Grande, in the town of Patos, Paraiba. Twenty-four animals were used, with ages varying between three and four months, being 12 females and 12 males, weaned and prevented against worms, receiving ad libitum water and controlled concentrate and roughage. The environmental variables were checked inside and outside the experiment place, as well as the physiological variables of all animals. Except for the humid bulb temperature, the variance analysis revealed shift effect (P<0.05) for all environmental variables. There was merely shift effect (P<0.05) for Cardiac Frequency and Rectal Temperature, and the averages of both, in the afternoon, overcame those observed in the morning. The obtained results based on the studied physiological and environmental variables conclude that crossbred goats, resulting of Boer (paternal) and Saanen (maternal), present a good resistance to heat, permitting their indication for the meat production in confinement on semiarid conditions.
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Alcohols and acids can be switched to produce ethers or esters by varying the alcohol to catalyst mol ratio, in a new etherification and esterification method using NbCl5/Al2O3 catalyst under "solvent free" conditions and promoted by MW (microwave) irradiation. A "two sites" mechanism for the reaction is proposed, in an attempt to clarify the tendency of the catalyst to be dependent on the alcohol alone during the esterification process. (c) 2008 Elsevier B.V. All rights reserved.
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This study was carried out to determine apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of DM, CP, GE, and their respective digestible content of degermed dehulled corn (Zea mays), citrus pulp, and soy (Glycine max) protein concentrate by pigs using the difference method. Thirty-two barrows (28.1 +/- 1.6 kg of BW) were fed a corn-soybean meal basal diet or 1 of 3 diets formulated by replacing 30% of the basal diet with 30% of 1 of the test feedstuffs for 11 d. Chromic oxide (0.3%) was included in the diets. Feces were collected from days 7 to 11 by grab sampling and ileal digesta were collected after pigs were slaughtered on day 12. The AID of DM and AID and ATTD of GE of degermed corn (77.4, 88.7, and 77.7%) were greater (P < 0.05) than those observed in citrus pulp (50.3, 86.5, and 55.8%) and in soy protein concentrate (63.5, 85.1, and 59.4%), which did not differ (P > 0.05). The ATTD of CP, total digestible CP, and total DE of soy protein concentrate (87.5%, 500 g/kg, and 3739 kcal/kg) were higher (P < 0.05) than the values in degermed corn (81.7%, 57.5 g/kg, and 3330 kcal/kg), which were greater (P < 0.05) than those in citrus pulp (60.5%, 39.5 g/kg, and 3223 kcal/kg). Total and ileal digestible DM, AID of CP, and ileal DE of degermed corn (782 g/kg, 673 g/kg, 70.7%, and 2913 kcal/kg) and soy protein concentrate (778 g/kg, 570 g/kg, 78.7%, and 2878 kcal/kg) were similar (P > 0.05) and greater (P < 0.05) than those in citrus pulp (737 g/kg, 436 g/kg, 50.6%, and 2081 kcal/kg). Ileal digestible CP of degermed corn (49.8 g/kg) and citrus pulp (33.0 g/kg) did not differ (P > 0.05) but were smaller (P < 0.05) than the value found in soy protein concentrate (434 g/kg). The DM and energy from degermed corn are more efficiently digested by the pig than those from soy protein concentrate and citrus pulp. Soy protein concentrate was the best protein source evaluated in this study.
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This study analyzed a population of the spider crab Epialtus brasiliensis, in regard to its size distribution, sex ratio and Sexual maturity. The study was conducted on a rocky shore in the Ubatuba region, state of Silo Paulo, Brazil, where a wide strip of algae covers the intertidal zone. A total of 378 specimens were obtained: 200 males (128 juvenile and 72 adult crabs) and 178 females (46 juveniles and 132 adults). Their Sizes ranged from 3.4 to 16.7 mm carapace length (CL). Taking into account that the pubertal and terminal molts are coincident in majid crabs, the maximum sizes attained by males and females are especially dependent on the factors that influence sexual maturity, mainly food resources, temperature and intraspecific competition. Males of E. brasiliensis occurred in all size classes, whereas females occurred only as far the 10th size class (12-13 min CL). file total sex ratio did not differ statistically from 1 : 1, but when the juvenile and adult specimens were analyzed separately the differences between sexes were significantly different, with higher proportions of immature males and mature females. The CL50 calculated for males and females was 10.4, and 6.9 min CL, respectively. Thus, males reach their sexual maturity at a larger size than females. This feature may be important for the reproductive strategy of this species, because larger males probably have greater reproductive Success.
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The serological detection of antibodies against human papillomavirus (HPV) antigens is a useful tool to determine exposure to genital HPV infection and in predicting the risk of infection persistence and associated lesions. Enzyme-linked immunosorbent assays (ELISAs) are commonly used for seroepidemiological studies of HPV infection but are not standardized. Intra-and interassay performance variation is difficult to control, especially in cohort studies that require the testing of specimens over extended periods. We propose the use of normalized absorbance ratios (NARs) as a standardization procedure to control for such variations and minimize measurement error. We compared NAR and ELISA optical density (OD) values for the strength of the correlation between serological results for paired visits 4 months apart and HPV-16 DNA positivity in cervical specimens from a cohort investigation of 2,048 women tested with an ELISA using HPV-16 virus-like particles. NARs were calculated by dividing the mean blank-subtracted (net) ODs by the equivalent values of a control serum pool included in the same plate in triplicate, using different dilutions. Stronger correlations were observed with NAR values than with net ODs at every dilution, with an overall reduction in nonexplained regression variability of 39%. Using logistic regression, the ranges of odds ratios of HPV-16 DNA positivity contrasting upper and lower quintiles at different dilutions and their averages were 4.73 to 5.47 for NARs and 2.78 to 3.28 for net ODs, with corresponding significant improvements in seroreactivity-risk trends across quintiles when NARs were used. The NAR standardization is a simple procedure to reduce measurement error in seroepidemiological studies of HPV infection.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Lead zirconate titanate powder, with Zr/Ti ratio of 50/50 was prepared by Pechini method after adding up to 10,0 mol% of Ba +2 and Sr +2 ions. Tetragonal phase is favored by the increase of barium and strontium concentration in the LiNbO 3 crystal lattice. The ratio c/a for tetragonal phase increases with the content of Ba +2 and Sr +2.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The structural characteristics of saturated silica sonogels were studied by means of small-angle x-ray scattering (SAXS) and thermogravimetric analysis (TG), after a long time of aging in saturated conditions. The sonogels were obtained by a sol-gel routine from ultrasound stimulated tetramethoxysilane (TMOS) hydrolysis carried out with the initial water/TMOS molar ratio (r) ranging from 2 to 10. The saturated sonogel structure can be described as composed by mass fractal-like aggregates (clusters) of primary silica particles, all imbibed in a liquid phase. The values of the mass fractal dimension (D) of the clusters was found all around 2.5, while the characteristic size of the clusters (ξ) was found generally increasing with r, going from approximately 2.3 nm (r = 2) to 4.5 nm (r = 10). The volume fraction of the clusters was estimated from the SAXS data. The results were compared to the values of weight loss fraction at the inflection point that has been found in the derivative of the TG curve, which should accounts for the instant in which the meniscus of the liquid phase penetrates into the clusters under a rapid evaporation process as in a TG test.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The relationship between the dielectric properties (dielectric constant, ε′, and loss factor, ε; activation energy, E a) and the ratio of epoxy resin (OG) to hardener of the epoxy resin thermosetting polymers was investigated. The amplitude of the ε″ peak decreases with increasing OG content until about 73 wt.% and slightly increases at higher OG content. The temperature of the position of the ε″ peak increases with the increasing of OG content, reaching maximum values for compositions in the range of 67 and 73 wt.%, and then it decreases sharply at higher OG content. The activation energy obtained from dielectric relaxation increased with increasing wt.% OG up to around 70 wt.%. Further increase in concentration of OG up to 83 wt.% reduced E a. The curves of tensile modulus and fracture toughness mechanical properties as a function of OG content presented a similar behavior. ©2006 Sociedade Brasileira de Química.
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This paper presents a new model for the representation of the electrodes filaments of fluorescent lamps, during their preheating, and an analysis capable to guide the design of the preheating process in electronic ballasts. The main improvement obtained with the lamp model is the accurate theoretical reproduction of the behavior of the Rh/Rc ratio during the preheating process. In addition, using the proposed methodology based on the lamp model, it is possible to set a proper preheating process to the electrodes filaments, without the necessity of exhaustive empirical adjustments in the prototype, reducing time and costs involved in the design of ballasts with preheating capabilities. © 2006 IEEE.