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An invisible displacement test was administered to cats in order to test the hypothesis that search behaviour in this species is influenced by their limited capacity for object permanence as well as by their previous experience with the environment. Experiment 1 compared three groups of cats in a five-choice hiding task in which the hiding places could be discriminated by their spatial positions. Two groups received a visible displacement training before the invisible displacement test and one group did not. Experiment 2 compared two groups of trained subjects in the same task, but the hiding places could be discriminated by spatial and visual cues. The results confirmed that cats are unable to solve problems with invisible displacements. The visible displacement training improved their performance, but was not sufficient to make them succeed. Experience with the hiding potential of the covers also gives more persistence to search behaviour. Finally, the distribution of search attempts is not determined by the proximity to the target and is influenced only partially by the subjects' previous experience. Like Stage 5 infants, cats rely mainly on their immediate perception. They search for an object in the last location they have seen it disappear or under the nearest cover from this location.  相似文献   
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Tested a 7-month, media-based, community intervention among Hispanics in San Francisco designed to change levels of information on the damaging effects of cigarette smoking and on the availability of culturally appropriate cessation services. Three community-wide surveys of Hispanics were conducted with independent random samples, two as baselines (n = 1,660 and 2,053) and one postintervention (n = 1,965). Results showed that changes in the level of awareness of cessation services had taken place after implementation of the intervention. Furthermore, those changes took place primarily among the less acculturated Spanish-speaking Hispanics who were the target of the intervention. The changes in information reported here demonstrate that a culturally appropriate information dissemination campaign that utilizes multiple channels can produce changes in a community's level of information even when the campaign is implemented for a relatively short period.  相似文献   
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How is meaning assigned to those terms in a theory which are remote from direct observational instantiation? Models and analogies play a role, but close examination of theories in high energy physics shows that the design of experimental apparatus also influences the interpretation of such terms. Certain apparatus favours certain kinds of effects, and this affects the way mathematical theories are interpreted. In particular track producing apparatus becomes involved with theories in which photonic terms are picked out in the theory. A further conceptual constraint is thus introduced. It is argued that this situation favours the interpretation of dispositional properties as affordances rather than as simple dispositions.  相似文献   
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The role accorded to the public by scientists and philosophers of science has undergone an essential historical change in the last three centuries. Public participation in (witnessing of) scientific experiments was considered an important requirement for 17th century experimenters (e.g. for Boyle or Pascal). The cognitive role played by lay persons was later substantially downgraded; witnessing went out of fashion, while science became more and more esoteric and a matter for experts only. Part of this process was that all scientific disciplines became intensively compartmentalized and in consequence a rather puzzling or even paradoxical situation appeared: that the scientists themselves were and are being reduced epistemically to the status of lay persons, outside of their proper field of expertise (as was pointed out by J. Hardwig). The paper deals with some cognitive aspects of this historical process.  相似文献   
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This study was designed to analyze whether Mental Rotation (MR) played a role as a mediating variable for sex-related differences in Visualization (VZ). Two psychometric tests measuring MR and VZ were applied to a representative sample of 309 males and 390 females in their last year of high school. Three non-zero correlations between sex and MR, sex and VZ, and MR and VZ were found, and the effect of sex on VZ was eliminated when MR was introduced as a covariable. When three subgroups of different VZ ability were made by dividing up the VZ distribution by the first and third quartiles, sex-differences were only found for the high-scorers group, for which previous results were replicated. Results clearly indicate that MR is a plausible mediator variable for sex differences in VZ when such differences do exist. Theoretical, methodological and practical consequences of these results are discussed.  相似文献   
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Tested a theoretical model on the effects of social role identity, illness intrusion, and competence on psychological well-being among 109 low-income Latinas with arthritis. All six roles studied were rated as highly important identities. Sex-role nontraditionalism was associated with less importance of the homemaker, mother, and grandmother roles. Negative affect increased as a function of intrusions into valued identities. Having important role identities contributed to feelings of competence (i.e., self-esteem and self-efficacy), which in turn, contributed to psychological well-being. Competence also mediated the effects of pain, identity, and illness intrusions on psychological well-being. Results suggest competence processes play an important role in well-being.  相似文献   
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