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91.
The aim of the current research was to clone and to characterize the partial 66 kDa streptavidin-bindingpeptide (SBP) found in the germinated embryos of Pisum sativum L. var. Alaska. The pea (P. sativum var. Alaska)embryos possess prominent 66 kDa SBPs that gradually disappeared after few hours of germination in germinatedembryos, but not in the cotyledons. The total RNA was isolated from embryos of P. sativum but could not be isolatedfrom the cotyledons. The partial nucleotides sequences of 66 kDa SBPs of embryonic stalk (P. sativum var. Alaska) werecloned and identified using pMOSBlue vector. 66 kDa (SBP) gene from the embryos of P. sativum var. Alaska possesses327 bp having an open reading frame (ORF) region in a part of the gene that encoded for 108 amino acids. Alignmentshowed similarity among 66 kDa SBPs P. sativum var. Alaska, with P. sativum seed biotinylated protein (SBP65) and P. sativum sbp65a mRNA with DNA distance matrix between 0.0094 to 1.2676. MALDI-TOF mass spectrometry analysisof 66 kDa (SBP) proteins showed it had similar short peptides to 19 proteins found in different organisms, especially Convicilin precursor, and the seed biotinylated protein in P. sativum. The alignment results of both nucleotide sequencesand amino acid residues either from cloning or MALDI-TOF-MS showed differences with related species, especially P. sativum. No mRNA was found in the cotyledons during seeds germination, which means no metabolic activities andthis part may act only as food reservoirs for growing newly embryos.  相似文献   
92.
The modelling problem of offshore towers is considered. A model is proposed which includes viscous and hydrodynamic drag damping and takes into account the stochastic nature of the problem. The model is decoupled into a set of modal equations by using the complex mode theory. A technique is developed to identify the modal parameters and the complex mode shapes by using the noisy excitation and response measurements. This technique is computationally efficient and accurate in the sense of minimizing a criterion function of the estimates variance. A simulation example is presented to demonstrate the results.  相似文献   
93.
Pb–Cu alloy coatings were electrodeposited on steel sheet cathodes from baths containing mixtures of lead nitrate, copper nitrate and sodium gluconate. Cathodic polarization, cathodic current efficiency and deposit composition were determined under different plating conditions. The results were consistent with the behaviour of a regular plating system with copper being the preferentially depositable metal. The lead (the less noble metal) content in the deposits increased with increase in current density and concentration of lead in the bath but decreased with increase in bath copper concentration. The structure and morphology of the as-deposited coatings were examined by X-ray, AES and SEM. The results showed that the deposits consist of a mixture of fine crystals of the two metals and the morphology of the deposits is mainly controlled by the composition of the deposit.  相似文献   
94.
Dispersibility of soy protein isolates was improved by adjusting pH to 12 and acidifying to pH 6.5. Alkaline treated isolates added to reconstituted nonfat milk reduced rennet induced coagulum firmness and syneresis more than did untreated soy protein isolates. Treated soy protein added to reconstituted nonfat dry milk reduced coagulum firmness and syneresis more than untreated soy protein. Soy protein interference with coagulum firmness and syneresis increased with an increase in pH becoming most severe at pH values above 11. Adjusting the pH of reconstituted NFDM in the absence of soy protein to pH 8 and holding for 30 min before adjusting it back to pH 6.5 had no effect on coagulum firmness or syneresis. However, higher pH treatments (pH 10 and above) caused reduction in coagulum firmness and in syneresis.  相似文献   
95.
Influence of gamma irradiation (1.5–10 kGy) and post-irradiation storage up to 20 days at 2 ± 2°C on some chemical criteria of tilapia and Spanish mackerel were studied. Total volatile basic nitrogen formation was lower in irradiated fish than in the unirradiated. Irradiation also caused a larger increase in thiobarbituric acid values which continued gradually during storage. Some fatty acids decreased by irradiation treatments at all doses. Thiamin loss was more severe at higher doses (≥4.5 kGy), whereas riboflavin was not affected. Alpha and gamma tocopherols of tilapia and alpha, beta, gamma, and delta tocopherols, in Spanish mackerel, decreased with increased dose and continued to decrease during 20-day post-irradiation storage.  相似文献   
96.
Control system design packages like MATLAB, MATRIXX, Control C, SIMNON, etc. have become essential ingredients of both undergraduate and graduate courses in the fields of systems and controls. The use of MATLAB and its companion toolboxes in teaching graduate and undergraduate courses was reported by many educators in the past. The experience with the use of SIMULINK and MATLAB in Intelligent Control Course is introduced which is offered to graduate students at Beijing University of Aeronautics and Astronautics (BUAA). The use of SIMULINK for simulation of intelligent control of their behavior is emphasized. The MATLAB features useful in this course are presented. How SIMULINK and MATLAB help in enhancing the students' understanding of the material and reducing the amount of time spent in performing computational homework assignments is discussed.  相似文献   
97.
Microwave heating of soybeans for 9 min decreased protein solubility from 80 to 17%, from 81 to 18%, and from 72 to 16% when deionized H2O, 0.6N NaCl and 0.4N CaCl2, were used as solvents, respectively. Experiments were conducted to determine ‘in vivo protein digestibility and metabolizable nitrogen using male Sprague-Dawley rats. The percentages of true digestibility were found to be 73, 84, 87 and 81 when the soybeans were microwave heated for 0, 9, 12 and 15 min, respectively. Microwave heating soybeans up to 15 min did not alter the fatty acids composition of the beans.  相似文献   
98.
Casein was enzymatically hydrolyzed for potential use in a hypoallergenic infant formula. Samples from the digest at different hydrolysis time (HT) intervals were tested for antigenicity, hydrophobicity, net charge (zeta potential), and emulsifying activity. Casein antigenicity loss could be approximated by three-phased first-order kinetics. Extensive antigenicity loss occurred during the first 10% of HT and relatively small changes occurred during the remaining 90% of HT. Hydrophobicity and emulsifying activity decreased, while the magnitude of the net charge increased (P <0.01) with increasing degree of hydrolysis. Strong correlations (r2≥ 0.89) were found among hydrophobicity, emulsifying activity and zeta potential.  相似文献   
99.
The effect of the addition of soy protein on the textural properties and microstructure of reconstituted nonfat dry milk coagulum with time after rennet addition was studied using an Instron Universal testing machine with a newly developed test cell, and by scanning electron microscopy. Soy protein added to reconstituted nonfat dry milk at 5% of the total solids resulted in a reduction in firmness, a decrease in syneresis and a looser microstructure of the coagulum at any given time up to two hours after rennet addition as compared to the control without added soy protein. An increase in the level of soy protein to 10 and 20% of the total solids resulted in a further reduction in coagulum firmness and in syneresis. Syneresis was also followed during changes in coagulum firmness. Analysis of the textural as well as microstructural data suggests that changes in coagulum firmness and syneresis of rennet-induced milk coagulums (with or without added soy protein) with time after rennet addition were associated with the extent to which casein micelles coalesced during coagulum formation. The Instron test and the syneresis test developed in this study were simple and practical.  相似文献   
100.
Reconstituted skimmed milk (10% TS) was ultrafiltered, and the permeate was concentrated threefold by reverse osmosis and then spray dried at different temperatures (145–195° C). The drying conditions had no effect on the moisture content or the major constituents of permeate powder. The powder was mainly lactose (85%) with 6.35460% ash. A small percentage of the lactose in the permeate powder was present as a-lactose. Sodium, potassium and citrate were present in high concentrations nearly equivalent to their average percentage in skimmed milk. The calcium, magnesium and inorganic phosphorus contents of permeate powder were also determined. The thiamine, riboflavin and niacin contents of permeate powder averaged 0.445, 0.947 and 0.729 mg/100 g respectively. The drying temperatures had no effect on the vitamin contents of the powder. The permeate powder had average Fe, Zn, Mn and Cu contents of 94.7, 21.1, 3.1 and 9.5 Fg/100 g respectively.  相似文献   
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