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931.
ABSTRACT: Grain of the soft white wheat cultivar Harus was harvested weekly from anthesis to maturity and fructooligosaccharides (FOS) contents were determined by reversed-phase high-performance liquid chromatography. Tests were carried out to determine the effect of adding immature wheat meal to a base flour of cultivar Russ (hard red spring) on the quality characteristics of bread. FOS content was also analyzed in baked bread, and the effect of transglutaminase in improving bread quality was examined. Marked decreases in FOS contents, such as 1-kestose and nystose, were observed with grain maturation. The overall quality of bread appeared to be acceptable, and the added FOS were retained after baking. 相似文献
932.
K M Cooper L Ribeiro P Alves V Vozikis S Tsitsamis G Alfredsson T L?vgren M Tuomola H Takalo A Iitia S S Sterk M Blokland D G Kennedy 《Food Additives & Contaminants》2003,20(9):804-812
Many zeranol immunoassay test kits cross-react with toxins formed by naturally occurring Fusarium spp. fungi, leading to false-positive screening results. This paper describes the evaluation and application of recently published, dry reagent time-resolved fluoroimmunoassays (TR-FIA) for zeranol and the toxin alpha-zearalenol. A ring test of bovine urine fortified with zeranol and/or alpha-zearalenol in four European Union National Reference Laboratories demonstrated that the TR-FIA tests were accurate and robust. The alpha-zearalenol TR-FIA satisfactorily quantified alpha-zearalenol in urine fortified at 10-30 ng ml(-1). The specificity-enhanced zeranol TR-FIA accurately quantified zeranol in the range 2-5 ng ml(-1) and gave no false-positive results in blank urine, even in the presence of 30 ng ml(-1) alpha-zearalenol. Zeranol TR-FIA specificity was demonstrated further by analysing incurred zeranol-free urine samples containing natural Fusarium spp. toxins. The TR-FIA yielded no false-positive results in the presence of up to 22 ng ml(-1) toxins. The performance of four commercially available zeranol immunoassay test kits was more variable. Three kits produced many false-positive results. One kit produced only one potential false-positive using a protocol that was longer than that of the TR-FIA. These TR-FIAs will be valuable tools to develop inspection criteria to distinguish illegal zeranol abuse from contamination arising from in vivo metabolism of Fusarium spp. toxins. 相似文献
933.
934.
In this paper, some biparametric models for an elastic foundation are proposed. It is assumed that the foundation has the shape of the wedge. The modeling procedure starts from the linear elasticity equations into which we introduce some simplifying assumptions based on the conceptions of decay functions. The simplified models are described by the ordinary differential equations. Stationary and nonstationary Green’s functions for the foundation considered are obtained by applying the Hankel and Laplace transform methods. An example of the interaction between the rigid plate and the elastic wedge foundation is studied. 相似文献
935.
Braithwaite Jason J.; Humphreys Glyn W.; Hodsoll John 《Canadian Metallurgical Quarterly》2003,29(4):758
Five experiments addressed the role of color grouping in preview search (D. G. Watson & G. W. Humphreys, 1997). Experiment 1 used opposite color ratios of distractors in preview and second search displays, creating equal numbers of distractors in each color group in the final display. There was selective slowing for new targets carrying the majority color of the old items. This effect held when there was no bias in the preview and only the second search set had an uneven color ratio (Experiment 2). In Experiment 3, participants had foreknowledge of the target color, and effects were shown over and above those due to color biases. Experiment 4 demonstrated negative color carryover even when previews changed color. Experiment 5 showed reduced color carryover effects when previews were presented more briefly. Collectively, the results provide evidence for inhibitory carryover effects in preview search based on feature grouping. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
936.
The operating conditions of this study are close to the typical operating conditions of flue gas desulfurization system in coal-fired power plants. The aim of this study is to investigate the absorption kinetics of SO2 and NO from simulated flue gas into an aqueous solution of acidic sodium chlorite using a bench-scale spraying column. The range of absorption rates measured in this study is between 1.91×10?11 and 9.59×10?10?mol?s?1?cm?2. The range of rate constants measured in this study is between 1.32×107 and 1.21×108?(L?mol?1)1.9?s?1, and the average rate constant is 6.16×107?(L?mol?1)1.9?s?1. The activation energy and frequency factor are 129 Kcal/mol (53.97 KJ/mol) and 6.93×1016?[(L/mol)1.9/s], respectively. 相似文献
937.
Sexual incentive motivation was evaluated in a procedure consisting of a large open field where incentive animals were confined behind wire mesh openings. When sexually inexperienced male rats (Rattus norvegicus) were exposed to the receptive female-male incentives, they spent more time close to the female. If the incentives were receptive female-nonreceptive female, the receptive female was preferred. However, when the alternatives were nonreceptive female-male, no preference was obtained. Castration abolished preference for the receptive female, and treatment with testosterone propionate restored it. Estradiol plus oil is as efficient as estradiol plus progesterone for giving the ovariectomized female incentive properties. The living female can be replaced with female odor. Sexual experience did not have any long-term effects on the female's incentive value, but immediately preceding limited sexual activity enhanced it. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
938.
939.
Torbj?rn Eltoft 《IEEE transactions on image processing》2005,14(11):1722-1735
In this paper, we introduce a new statistical distribution for modeling non-Rayleigh amplitude statistics, which we have called the Rician inverse Gaussian (RiIG) distribution. It is a mixture of the Rice distribution and the inverse Gaussian distribution. The probability density function (pdf) is given in closed form as a function of three parameters. This makes the pdf very flexible in the sense that it may be fitted to a variety of shapes, ranging from the Rayleigh-shaped pdf to a noncentral chi2-shaped pdf. The theoretical basis of the new model is quite thoroughly discussed, and we also give two iterative algorithms for estimating its parameters from data. Finally, we include some modeling examples, where we have tested the ability of the distribution to represent locale amplitude histograms of linear medical ultrasound data and single-look synthetic aperture radar data. We compare the goodness of fit of the RiIG model with that of the K model, and, in most cases, the new model turns out as a better statistical model for the data. We also include a series of log-likelihood tests to evaluate the predictive performance of the proposed model. 相似文献
940.
Novel floating-patch micro-electro-mechanical system (MEMS) antennas are proposed for millimetre-wave applications. The floating-patch MEMS antennas are fabricated on a high resistivity silicon (HRS) substrate using surface micromachining technology. Simulation and experimental results for reflection coefficients and radiation patterns are presented. 相似文献