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81.
El-Shenawee M 《IEEE transactions on bio-medical engineering》2004,51(1):35-44
This paper presents an intensive numerical study of the resonance scattering of malignant breast cancer tumors. The three-dimensional electromagnetic model, based on the equivalence theorem, is used to obtain induced electric and magnetic currents on breast and tumor surfaces. The results show that the nonspherical malignant tumor can be characterized, based on its spectra, regardless of orientation, incident polarization, or incident or scattered directions. The spectra of the tumor depend solely upon its physical characteristics (i.e., shape and electrical properties); however, their locations are not functions of the depth of the tumor beneath the breast surface. This paper can be a guide in the selection of the frequency range at which the tumor resonates to produce the maximum signature at the receiver. 相似文献
82.
Elena Suárez‐Bonnet Magda Carvajal Ignacio Méndez‐Ramírez Pável Castillo‐Urueta Josefina Cortés‐Eslava Sandra Gómez‐Arroyo José María Melero‐Vara 《Journal of food science》2013,78(11):T1822-T1829
Rice is an important cereal but it is often contaminated with aflatoxins (AFs). The purpose of this study was to identify and quantify AF (B1, B2, G1, and G2) in 67 rice samples cultivated in Mexico and Spain, and from imported crops collected in 2008 and 2009. The methodology was validated, the rice samples were concentrated and purified with immunoaffinity columns and were quantified by high‐pressure liquid chromatography (HPLC). The average total AF (AFt) in the Spanish rice was 37.3 μg/kg, the range was from 1.6 to 1383 μg/kg, the most contaminated samples being from San Juan de Aznalfarache, Sevilla (AFt = 138.6 μg/kg), from Tortosa, Tarragona (AFt = 104.6 μg/kg), and Calasparra, Murcia (AFt = 103.9 μg/kg). The rice imported from France to Spain had AFt of 26.6 μg/kg and from Pakistan AFt of 18.4 μg/kg, showing less AF contamination than the local one. The rice which originated from Mexico contained (AFt = 16.9 μg/kg), and those imported from the United States (AFt = 14.4 μg/kg) and Uruguay (AFt = 15.6 μg/kg). The imported rice had better quality in terms of the presence of AFs. 相似文献
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A sensory evaluation of croissants and magdalenas (Spanish muffins) has been carried out to compare them with the same products with phytosterol esters, α-tocopherol and β-carotene added. The subjects were habitual consumers and no differences were detected between the two types of product. Furthermore, the chemical composition (53 parameters) of croissants (n = 9) and muffins (n = 8) marketed in Spain, has been analysed and a nutritional evaluation performed on these products with regard to their suitability as carriers of the functional ingredients mentioned above. The chemical compositions are not similar and the main difference is related to fatty acids. Croissants are characterized by a high percentage of saturated fatty acids (SFA) (44.0 ± 3.8%), and the presence of trans fatty acids (TFA) (4.29 ± 1.48%). This contrasted with the high content of polyunsaturated fatty acids (PUFA) (62.1 ± 1.5%) in the muffins and the near absence of TFA (0.16 ± 0.23%). Furthermore, the large differences between the compositions of the commercial croissants and muffins (magdalenas) and, therefore, between their nutritional values, makes the use of phytosterols recommendable in muffins and, in general, in all bakery products in which the SFA + TFA represent ?20% of the fatty acid fraction. 相似文献
84.
Kris Villez Gürkan Sin Peter A Vanrolleghem Magda Ruiz Joan Colomer Christian Rosén Peter A Vanrolleghem 《Water science and technology》2008,57(10):1659-1666
A methodology based on Principal Component Analysis (PCA) and clustering is evaluated for process monitoring and process analysis of a pilot-scale SBR removing nitrogen and phosphorus. The first step of this method is to build a multi-way PCA (MPCA) model using the historical process data. In the second step, the principal scores and the Q-statistics resulting from the MPCA model are fed to the LAMDA clustering algorithm. This procedure is iterated twice. The first iteration provides an efficient and effective discrimination between normal and abnormal operational conditions. The second iteration of the procedure allowed a clear-cut discrimination of applied operational changes in the SBR history. Important to add is that this procedure helped identifying some changes in the process behaviour, which would not have been possible, had we only relied on visually inspecting this online data set of the SBR (which is traditionally the case in practice). Hence the PCA based clustering methodology is a promising tool to efficiently interpret and analyse the SBR process behaviour using large historical online data sets. 相似文献
85.
In problem-solving research, insights into the relationship between monitoring and control in the transfer of complex skills remain impoverished. To address this, in 4 experiments, the authors had participants solve 2 complex control tasks that were identical in structure but that varied in presentation format. Participants learned to solve the 2nd task on the basis of their original learning phase from the 1st task or learned to solve the 2nd task on the basis of another participant's learning phase. Experiment 1 showed that, under conditions in which the participant's learning phase was experienced twice, performance deteriorated in the 2nd task. In contrast, when the learning phases in the 1st and 2nd tasks differed, performance improved in the 2nd task. Experiment 2 introduced instructional manipulations that induced the same response patterns as those in Experiment 1. In Experiment 3, further manipulations were introduced that biased the way participants evaluated the learning phase in the 2nd task. In Experiment 4, judgments of self-efficacy were shown to track control performance. The implications of these findings for theories of complex skill acquisition are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Barbara Wituszynska und Magda Telegdy-Kováts 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1968,135(6):326-327
Ohne Zusammenfassung 相似文献
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Magda Marcon Markus Weiger Daniel Keller Moritz C. Wurnig Christian Eberhardt Daniel Eberli Andreas Boss 《Magma (New York, N.Y.)》2016,29(6):853-862