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101.
C Daumas-Duport ML Tucker H Kolles P Cervera F Beuvon P Varlet N Udo M Koziak JP Chodkiewicz 《Canadian Metallurgical Quarterly》1997,34(1):61-78
Myocardial perfusion scintigraphy is a noninvasive diagnostic method for the evaluation of patients with suspected or proven coronary artery disease (CAD). We utilized case-based reasoning (CBR) methods to develop the computer-based image interpretation system SCINA which automatically derives from a scintigraphic image data set an assessment concerning the presence of CAD. We compiled a case library of 100 patients who underwent both perfusion scintigraphy and coronary angiography to document or exclude the presence of CAD. The angiographic diagnosis of the retrieved nearest neighbor match of a scintigraphic input case was selected as the CBR diagnosis. We examined the effects of input data granularity, case indexing, similarity metric, and adaptation on the diagnostic accuracy of the CBR application SCINA. For the final prototype, sensitivity and specificity for detection of coronary heart disease were 98% and 70% suggesting that CBR systems may achieve a diagnostic accuracy that appears feasible for clinical use. 相似文献
102.
RM Summers J Andrasko-Bourgeois IM Feuerstein SC Hill EC Jones MK Busse B Wise KE Bove BA Rishforth E Tucker TL Spray JM Hoeg 《Canadian Metallurgical Quarterly》1998,98(6):509-518
Hepatitis C chronically infects approximately 1.5% of Americans and is the most common clinical problem facing hepatologists. Since the virus was initially described in 1989, development of an effective therapy has been challenging. Although several different therapeutic agents have been used, no therapy has been shown to reliably eradicate the virus. Interferon-alpha, a cytokine with immunostimulatory and anti-viral properties, has become the therapy of choice for patients with chronic hepatitis C infection. Trials assessing the efficacy of interferon-alpha have characterized host and viral factors predictive of responses to treatment. A thorough understanding of these predictive factors is requisite to providing cost-effective therapeutic decisions for the patient with chronic hepatitis C infection. 相似文献
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The erucic acid content of broccoli florets, sprouts, and seeds was found to be about 0.8, 320, and 12100 mg/100 g, respectively. Using the erucic acid limit established for canola oil in the U.S.A. and Canada as a guideline, the estimated dietary intake of erucic acid from florets and sprouts was considered of little consequence, whereas in seeds a relatively small amount (about 35 g/wk) equaled our calculated exposure limit for erucic acid. Additionally, the most complete fatty acid distribution yet published for the various forms of broccoli are presented. 相似文献
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A Galerkin finite element solution is developed for the flow of fiber suspensions. Primary variables are velocity, pressure, and a second‐order tensor describing the fiber orientation. The model treats the orientation as three‐dimensional, includes fiber—fiber interaction effects, and uses an orthotropic closure approximation. The flow and orientation are strongly coupled through an orientation‐dependent constitutive equation. We explore the effect of this coupling on the fluid mechanics of fiber suspensions by studying three flows: an axisymmetric contraction, an axisymmetric expansion, and a center‐gated disk. Coupling enhances the corner vortex in the contraction, in quantitative agreement with published experiments and calculations. The expansion results demonstrate that the aligned‐fiber approximation is not valid for this flow. In the center‐gated disk the effects of coupling are modest and are only noticeable near the center of the disk. This supports the use of decoupled models for injection molding in thin cavities. 相似文献
107.
Tucker Sean; Chmiel Nik; Turner Nick; Hershcovis M. Sandy; Stride Chris B. 《Canadian Metallurgical Quarterly》2008,13(4):319
In the present study, we modeled 2 sources of safety support (perceived organizational support for safety and perceived coworker support for safety) as predictors of employee safety voice, that is, speaking out in an attempt to change unsafe working conditions. Drawing on social exchange and social impact theories, we hypothesized and tested a mediated model predicting employee safety voice using a cross-sectional survey of urban bus drivers (n = 213) in the United Kingdom. Hierarchical regression analysis showed that perceived coworker support for safety fully mediated the relationship between perceived organizational support for safety and employee safety voice. This study adds to the employee voice literature by evaluating the important role that coworkers can play in encouraging others to speak out about safety issues. Implications for research and practice related to change-oriented safety communication are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Results of investigation into the relationship between friction in the O-ring type seal and gauge pressure at the commencement of linear motion of a shaft are presented and discussed. A number of different O-ring materials were studied and the lowest friction under dry conditions was found to be produced by a PTFE-encapsulated silicone seal. The effect of a number of lubricating fluids on friction in the seal was also studied and the results obtained are included. 相似文献
110.