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The masticatory performance of an individual has been quantified by determining the particle sizes of the comminuted food. Optosil, a silicon rubber, has been used as an artificial test food in clinical studies, because it has reproducible textural properties. A comparison between Optosil and several natural foods was made by measuring textural properties of Optosil, turnip, carrot, Gouda cheese and peanut. Several types of probes were used to imitate the cusp form of the teeth. Force-deformation plots revealed similar maximum firmness for Optosil, turnip and carrot, whereas peanut showed a larger firmness. The force needed to crush Optosil is much larger than for the natural foods, but it is well within the physiological range of healthy subjects. The reproducibility of the textural properties is better for Optosil than for the natural foods. The particle size distribution of Optosil broken by a testing machine was compared with the results obtained during chewing. 相似文献
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Successful cytologic diagnosis of cholangiocarcinoma from within a recently placed biliary Wallstent
A six year old boy with an epicardial pacing lead since infancy presented with thoracic pain triggered by movement. The pain was thought to be musculoskeletal, but two weeks later he collapsed and died in ventricular fibrillation. Necropsy showed strangulation of the ventricular apex by the epicardial lead. 相似文献
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A. J. C. DE O. BARROS 《Coloration Technology》1966,82(1):3-7
Factors are summarised which led to the development of screen and copper–roller techniques as two complementary systems for textile printing, and problems are explained which delayed the commercial exploitation of the rotary screen. Features of the print–paste applicator and the screen construction are studied. Recent improvements in durability and versatility of screens are examined, and novel fields of application for the rotary screen, particularly in duplex printing, are reviewed. 相似文献
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Abstract A generalized information system has recently been proposed 相似文献
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Abstract In this article, we first point out the advantages and limitations of the keywords filtering techniques and the standard automatic clustering techniques for group technology applications. We consider, then, a product, or more generally an item, as a conjunction of symbolic attributes. We present a new method to recognize homogeneous families of products and to interpret the families by extraction of their concepts. Finally, the method is applied to analyze a population of 1010 mechanical parts. 相似文献