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861.
862.
Arthur A. van Hoff Tim Niblett David G. Rowlands Alan Flook Peter I. Payne Sean McKee 《Knowledge》1988,1(5):292-300
A powerful technique, two dimensional gel electrophoresis, has recently become available for the analysis of biological material. This technique allows the proteins of a sample to be mapped on a two-dimensional polyacrylamide gel. The research outlined here involves a multi-disciplinary approach to the semi-automatic comparison of two gels of biologically similar materials. The aim of the project is to identify the significant differences between the gels and point them out to the electrophoresis expert. This job, when done by hand, can be time consuming, since the gels are distorted and can contain hundreds of protein spots. Automatic analysis of 2D gel separations has proved to be extremely difficult using statistical methods. Non-reproducibility of gel separations is also difficult to overcome using automatic systems. However, the human eye is extremely good at recognizing patterns in images, and human intervention in semi-automatic computer systems can reduce the computational complexity. This paper focuses on the intelligent knowledge-based systems aspects of the project, and in particular the work of the first author. The results demonstrate that the semi-automatic approach can produce reliable results quickly. Further work, beyond the scope of this paper, focuses on creating a database of gels for comparison. 相似文献
863.
864.
865.
G. Harvey Anderson 《Critical reviews in food science and nutrition》1994,34(5-6):435-440
Dietary guidelines of the U.S. and Canada recommend that 55% of dietary calories of individuals should come from carbohydrates, especially complex carbohydrates. However, they generally fail to describe how much should come from complex carbohydrates. Undoubtedly, this is because of confusion about the composition of complex carbohydrate foods and incomplete knowledge of the health benefits of all components of grain products. With the intent of shifting dietary food selection to increase carbohydrate consumption above the current 46% of calories, food guides recommend 5 to 12 servings per day from grain products. Current estimated intake for adults is between four to five servings of grain products, of which less than one is from whole grain, in an average 2000‐kcal adult diet. To follow the advice of the U.S. Food Guide Pyramid, which suggests half the bread (grains) group should be whole‐grain products, adult Americans should increase their intake of whole‐grain products four‐ to fivefold and double their intake of total grain products. 相似文献
866.
Capital cost correlations are given for liquid moving equipment. Correlations available in the literature and current data from suppliers, contractors, consultants and industry are compared on a consistent basis. Forty-three graphs show the relative magnitudes of the different correlations, and the recommended correlation for each type of equipment is given. Some factors are given on the costs of installing liquid moving equipment. 相似文献
867.
868.
Summary SEMANOL is a practical programming system for writing readable formal specifications of the syntax and semantics of programming languages. SEMANOL is based on a theory of semantics which embraces algorithmic (operational) and extensional (input/output) semantics. Specifications for large contemporary languages have been constructed in the formal language, SEMANOL (73), which is a readable high-level notation. A SEMANOL (73) specification can be executed (by an existing interpreter program); when given a program from the specified language, and its input, the execution of the SEMANOL (73) specification produces the program's output. The demonstrated executability of SEMANOL (73) provides important practical advantages. This paper includes discussions of the theory of semantics underlying SEMANOL, the syntax and semantics of the SEMANOL (73) language, the use of the SEMANOL (73) language in the SEMANOL method for describing programming languages, and the contrast between the Vienna definition method (VDL) and SEMANOL. 相似文献
869.
Reynolds Ralph E.; Standiford Sally N.; Anderson Richard C. 《Canadian Metallurgical Quarterly》1979,71(2):183
43 undergraduates read a text either with or without inserted questions. Although there was no overall reading time difference between the question or no-question groups, Ss who received inserted questions spent more time on the parts of the text that contained information of the type needed to answer the questions. Question groups performed better, relative to controls, on posttest items that repeated inserted questions and also on new posttest items from the same categories as the inserted questions. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
870.
The area under the liver was dissected in 27 human autopsy specimens to search for lymph nodes in the fissures. Nodes were present in all instances. They were in the transverse fissure, posterior to the portal vein, posterior to pars transversus of the left portal vein and associated with the left hepatic artery. The size varied from 2 millimeters to 2 centimeters. Each node was histologically confirmed. Nodes were infrequent and small on the right. Nodes were not found between the portal vein, hepatic artery and bile ducts in the fissures. Nodes were found outside the fissures in the fascia between the bile duct and hepatic artery. Occlusion of the portal vein and hepatic artery could be expected before occlusion of the bile duct. Node enlargement in the transverse fissure is anticipated as a rare cause of jaundice. 相似文献