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831.
Neale John M.; McIntyre Curtis W.; Fox Robert; Cromwell Rue L. 《Canadian Metallurgical Quarterly》1969,74(5):593
Compared the span of apprehension for 2 schizophrenic groups (15 good premorbid paranoid and 15 poor premorbid nonparanoid) with the span for a normal control group (15 hospital aides) by a forced-choice letter-recognition method analogous to signal-detection methodology. This procedure, in conjunction with a quantitative model of the span, provides an indirect but relevant measure insensitive to variance imposed by nonperceptual systems. The span size was the same for all 3 groups when visual "noise" was absent. In the presence of noise, span size for both schizophrenic groups was about 50% smaller than that of the control group. It is argued that the reduction in span represents a true deficit in attention, uncontaminated by extraneous variables. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Polybutadiene rubbers, filled with polydichlorostyrene or polystyrene latices having spherical diameters of approximately 500Å, were examined by small angle x-ray scattering. The filler latices were examined by x-ray scattering as a function of strain. The sample elongations ranged up to 400 percent. An analysis of the scattering of the polydichlorostyrene filler latices showed that there was deformation of the filler particles up to 25 percent. Such a deformation is not expected on the basis of the mechanical properties of bulk glassy polydichlorostyrene. However, deformation into ellipsoids of revolution is consistent with the x-ray evidence. The deformation of the latices is reasonable. 相似文献
834.
EK Silberman E Vivaldi J Garfield RW McCarley JA Hobson 《Canadian Metallurgical Quarterly》1980,191(1):215-224
Two physical factors affecting the behavioral effects of drugs microinjected into the pontine tegmentum have been studied. Reducing the volume of vehicle produced a dramatic enhancement of the capacity of the long-acting cholinergic agent carbachol to induce desynchronized (D) sleep-like behavior (Dcarb). Enhancement of Dcarb was also achieved by substitute passive diffusion for active pumping of a given volume of carbachol solution. Controlling these two physical factors makes Dcarb a compelling experimental model for the study of D sleep mechanisms. The results also give support to the concept of a localized population of cholinoceptive neurons in the pontine reticular formation whose activation is a key step in the generation of physiological D. 相似文献
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VLADIMÍR ŽENIŠEK 《International journal of control》2013,86(3):505-512
A universal algorithm is presented in the paper which makes it possible to find out whether a given relative extremum of a scalar-valued function of a vector argument is also the absolute one and, if not, to find a point at which a relative extremum-seeking procedure can be restarted in order that a better relative extremum—i.e. one at which the given function takes a less, alternatively greater, value—may be obtained. Repeated application of the described procedure in combination with an arbitrary relative extremum-seeking procedure leads to determining the absolute extremum. The possibility of application to stochastic and integer programming problems is discussed. 相似文献
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