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31.
Transparent layer constancy 总被引:1,自引:0,他引:1
W Gerbino C I Stultiens J M Troost C M de Weert 《Journal of experimental psychology. Human perception and performance》1990,16(1):3-20
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable. 相似文献
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Molecular sequence data, made available in the last 15 years or so, have led to the classification of living cells into three phylogenetic domains: Bacteria, Archaea, and Eucarya. All the organisms that have been tested belonging to either domain were capable of mounting a stress response with essentially the same characteristics, regardless of the stressor. The protagonists in the cell's stress response are the stress genes and their protein products. Some of the latter are molecular chaperones. Under physiological conditions, these chaperones aid other cellular proteins to fold properly and achieve a native -functional- configuration, and to translocate from the place of synthesis to the cell's locale in which they will operate. In a stressed cell, the stress proteins that are chaperones protect other molecules from denaturation and help those partially damaged to regain a functional configuration. Thus, cell death is avoided and recovery is enhanced. The study of stress genes and proteins has progressed considerably in organisms belonging to the domains Bacteria and Eucarya. Less is known about the archaeal stress genes. Here, research with an organism from the Archaea is discussed, focusing on the stress genes of the hsp70 (dnaK) locus. Future perspectives for basic and applied research within the health sciences and biotechnology industries are presented. 相似文献
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Kosslyn suggested a dissociation of two kinds of spatial representations: categorical and coordinate, the former computed by the left hemisphere and the latter by the right hemisphere. In addition, with practice, a “categorization” of the coordinate computation would appear. These suggestions resulted largely from an experiment, replicated by others, in which the subjects had to estimate the relative position of a dot and a line by giving an oral response, and feedback was provided. The present series of five experiments was an attempt to test whether this finding could be generalized, under several methodological manipulations, some of which have already been used by researchers in separate studies. In the five experiments, accuracy was a more contributive dependent variable than correct latencies, and practice effects on the task × field interaction were not verified. Experiments 1–3 concerned the kind of response. When a manual instead of an oral response was required (Experiment 1;n= 32 Ss), the expected dissociation was observed (as well as when the latency of responses made by the right hand were studied). When the number of oral responses was increased from two (a binary choice) to eight, the dissociation was still observed for accuracy but disappeared when a more liberal criterion of accuracy was used to reduce the considerable task effect (Experiment 2;n= 32 Ss), or when response requirements were equated for both tasks (Experiment 3;n= 32 Ss). In Experiment 4 (n= 32 Ss), a manual response was called but the feedback was removed and the task dissociation disappeared. Finally, the task dissociation observed in Experiment 1 was not verified when a sample of elderly subjects was enrolled (Experiment 5;n= 32 Ss). However, age per se was the source of an interesting additional dissociation since only the coordinate computation was age sensitive. Our results suggest that the dissociation proposed by Kosslyn between the computation of categorical vs coordinate spatial relationships is highly unstable and sensitive to subtle methodological factors (vocal vs manual response, presence vs absence of feedback, binary vs “continous” response, age) which could preclude its general application. 相似文献
34.
W. M. de Muynck 《Synthese》1995,102(2):293-318
The axiomatic approaches of quantum mechanics and relativity theory are compared with approaches in which the theories are thought to describe readings of certain measurement operations. The usual axioms are shown to correspond with classes of ideal measurements. The necessity is discussed of generalizing the formalisms of both quantum mechanics and relativity theory so as to encompass more realistic nonideal measurements. It is argued that this generalization favours an empiricist interpretation of the mathematical formalisms over a realist one. 相似文献
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Henry Garrett (1961), a president of the American Psychological Association, claimed that “the equalitarian dogma,” the belief that Blacks and Whites are genetically equal in cognitive ability, was the “scientific hoax of the century.” Since then, the dogma has become more ingrained, despite increased contrary evidence. The dogma has been perpetuated by intimidation as well as by pious thinking. Its long endurance is a scandal of great proportion and illuminates how science works, and sometimes does not. I discuss (a) current international data on race differences; (b) their genetic and evolutionary origins; (c) political fallout from my presentations; (d) corruption of scholarship that has occurred, illustrated partly by the example of Cyril Burt; and (e) what should be done to improve matters. 相似文献
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FROM BLOBS TO BOUNDARY EDGES: 总被引:13,自引:1,他引:12
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