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11.
Holden Ronald R.; Woermke Christina; Fekken G. Cynthia 《Canadian Metallurgical Quarterly》1993,25(1):1
Evaluated the effects of increasing scale reliability and of priming dimensional activation on the construct validity of personality test item differential response latencies. 93 undergraduates were computer-administered items from the 3 lengthened scales of the Personality Research Form. Findings show that differential response latencies can demonstrate remarkably strong evidence for their construct validity. In addition, the priming of personality traits may enhance the construct validity of their corresponding differential response latencies. Results support a model of test item responding where differential item response latencies reflect the interaction of an individual's schema with test item content. (French abstract) (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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A method for estimating the phase current unbalance in a multiphase buck converter is presented. The method uses the information contained in the voltage drop at the input capacitor's effective series resistance (ESR) to estimate the average current in each phase. Although the absolute estimation of the currents depends on the value of the ESR and is therefore not absolutely accurate, the relative estimates of the currents with respect to one other are shown to be very accurate. The method can be implemented with a low-rate down-sampling A/D converter and is not computationally intensive. Experimental results are presented, showing good agreement between the estimates and the measured values. 相似文献
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Luciana Juncioni de Arauz Angela Faustino Jozala Gabriel Soares Pinheiro Priscila Gava Mazzola Adalberto Pessoa Júnior Thereza Christina Vessoni Penna 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(3):325-328
BACKGROUND: Nisin is a commercially available bacteriocin produced by Lactococcus lactis ATCC 11454 and used as a natural agent in the biopreservation of food. In the current investigation, milk whey, a byproduct from dairy industries was used as a fermentation substrate for the production of nisin. Lactococcus lactis ATCC 11454 was developed in a rotary shaker (30 °C/36 h/100 rpm) using two different media with milk whey (i) without filtration, pH 6.8, adjusted with NaOH 2 mol L?1 and without pH adjustment, both autoclaved at 121 °C for 30 min, and (ii) filtrated (1.20 µm and 0.22 µm membrane filter). These cultures were transferred five times using 5 mL aliquots of broth culture for every new volume of the respective media. RESULTS: The results showed that culture media composed of milk whey without filtration supplied L. lactis its adaptation needs better than filtrated milk whey. Nisin titers, in milk whey without filtration (pH adjusted), was 11120.13 mg L?1 in the second transfer, and up to 1628‐fold higher than the filtrated milk whey, 6.83 mg.L?1 obtained in the firstt transfer. CONCLUSIONS: Biological processing of milk byproducts (milk whey) can be considered a profitable alternative, generating high‐value bioproducts and contributing to decreasing river disposals by dairy industries. Copyright © 2008 Society of Chemical Industry 相似文献
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ME Sanders 《Canadian Metallurgical Quarterly》1998,80(4):S213-S218
Curiosity about probiotic bacteria is high. This is not surprising given the rapid growth of the natural products market in the USA, which was 22% in 1995 (New Hope Natural Media, Boulder, CO). Although probiotic cultures are only one component of that market, this trend shows that consumers in the USA are increasingly taking a pro-active stance towards their health and are purchasing products not only to eliminate what is perceived as dietary negatives but to increase the levels of dietary positives (Wrick, 1995). This shift in consumer attitude bodes well for the development of the American probiotic market. This article describes the composition, promotion and labelling of probiotic-containing products, discusses attributes of commercial probiotic bacteria, and estimates the size of the probiotic market in the USA. This market information was obtained from several published (Anon, 1996a,b) and unpublished but commercially available (SPINS Information Services, San Francisco, CA and New Hope Natural Media, Boulder, CO) sources. 相似文献
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Lyapunov-based control for switched power converters 总被引:1,自引:0,他引:1
Beginning with fundamental properties such as passivity or incremental passivity of the network elements comprised by a switched power converter, the nominal open-loop operation of a broad class of such converters is shown to be stable in the large via a Lyapunov argument. The obtained Lyapunov function is then shown to be useful for designing globally stabilizing controls that include adaptive schemes for handling uncertain nominal parameters. Numerical simulations illustrate the application of this control approach in DC-DC converters 相似文献
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Understanding information sharing is an important challenge to modern organizations, and is likely to be increasingly considered when IT investment decisions are made world-wide. Our research study investigated the influence of cultural factors on information sharing in China. It was postulated that social network structures such as guanxi, Confucian dynamism, and collectivism could explain the degree to which information sharing took place between people in China. It was found that guanxi, Confucian dynamism, and collectivism all had a significant influence on information sharing. 相似文献
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JP Gagliardi RE Nettles DE McCarty LL Sanders GR Corey DJ Sexton 《Canadian Metallurgical Quarterly》1998,26(5):1165-1168
The effect of age on the presentation and outcome of infective endocarditis (IE) is unclear. Many of the available data are based on analyses of mixed populations of patients including intravenous drug users or those with prosthetic valve endocarditis or native valve IE. We used the Duke criteria to compare the characteristics of 44 episodes of definite native valve IE in elderly patients (> 64 years old) with the characteristics of 64 similarly defined episodes of native valve IE in younger, nonintravenous-drug-using adult patients (> 29 years and < 60 years old). Our data suggest that the clinical presentation, characteristics, and outcome of native valve IE are similar for elderly patients and younger adult patients, although elderly patients were hospitalized an average of 12 days longer. Although we found that the occurrence of renal failure and cerebral embolism during an episode of IE was associated with higher rates of death (odds ratios, 4.8 and 4.0, respectively), age was not a significant contributor to mortality. 相似文献