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91.
Trained 120 grain beetles to make a turning response in a T maze with a bright light as negative reinforcement. Ss were given 2 consecutive trials/day, and after a delay of either 5 sec, 30 sec, 1 min, 2.5 min, or 5 min following the 2nd trial, they were cooled to 35. F until the next day's trials. Hypothermia imposed at intervals of 1 min or less after a set of learning trials was found to disrupt acquisition (p 相似文献
92.
Begins with the unusual assumption that it may be possible to allocate merit, and then raises the question of how merit shall be distributed (i.e., Who merits an increase in merit?). This question is the basis for a discussion of distributive justice in education which focuses on the distribution of symbols of educational merit—grades. The article discusses the social function of the artificially created shortage of high marks and considers different characteristics of grading systems. The effects of cooperative and competitive distributive systems are summarized. The article concludes with the question: If the competitive-hierarchical atmosphere (induced by the competitive distribution system used wih respect to grades in the classroom) is not good for our children, is it good for us? (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A circuit for the measurement of biological time intervals from 0.1 ms to 10 s is described. This device accepts biopotentials, stimuli, or transducer signals to produce an instantaneous dc voltage readout proportional to the time between two successive input signals. Digital preconditioning and analog integration are used to simplify the design. 相似文献
95.
bis-Phosphatidic acid from developing soybean was completely hydrolyzed with phospholipase A2 (lyophilized venom from Ophiophagus hannah) to yield lyso-bis-phosphatidic acid and free fatty acids. It is suggested that
soybean bis-phosphatidic acid is derived from sn-3-glycerophospho-sn-3′-glycerol. 相似文献
96.
Summary The effect of strain and location grown on the sesmin, sesamolin, and sesamol content of oils from sesame seed chosen to represent
a wide variety of genetic material is reported. Only differences in sesamin content due to strain were significant.
Three of four oils exposed as the oil to 100°F. became rancid in two to three months. Rancidity of the oil was accompanied
by lesser sesamin and sesamolin contents, and the ultraviolet spectrum of the oil was much altered. Oil from seed exposed
as the seed to the same conditions for six months did not become rancid even though most of the seeds were damaged in threshing.
The sesamol content of all the oils subjected to the accelerated ageing procedure increased, but the increase was greatest
in the rancid oils.
Frost damage of sesame seed markedly diminished the sesamin and sesamolin content of the oil. 相似文献
97.
R. Dennis Cook Nate Wetzel José D. Bermúdez J. De La Horra Frank Critchley Michael Lavine Ker-Chau Li R. E. McCulloch Sally C. Morton X. Shen Sanford Weisberg S. Zacks 《TEST》1993,2(1-2):33-100
Summary We investigate the extent to which it may be possible to carry out a regression analysis using graphics alone, an idea that
we refer to asgraphical regression. The limitations of this idea are explored. It is shown that graphical regression is theoretically possible with essentially
no constraints on the conditional distribution of the response given the predictors, but with some conditions on marginal
distribution of the predictors. Dimension reduction subspaces and added variable plots play a central role in the development.
The possibility of useful methodology is explored through two examples.
Read before the Spanish Statistical Society at a meeting organized by the Carlos III University of Madrid on Wednesday, April
21, 1993 相似文献
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