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51.
Marja Alestalo’s 《Knowledge, Technology, and Policy》1993,6(1):52-66
Finland has followed the Scandinavian model of the welfare state in which the level of state activism is high, the economic
pressures on the scientific activities are strong, and the left-wing parties and the Center Party have formulated the main
ideas. In the 1970s welfare ideology was adopted in science policy by emphasizing the promotion of socially relevant scientific
activities and the expansion of the university system as a means of effecting equal opportunity. Currently, the trend is toward
a mixed welfare economy. Programs have been prepared in spite of the radical cut in government expenditure, and without a
consideration of the long-term consequences. 相似文献
52.
When an observer views a moving scene binocularly, both motion parallax and binocular disparity provide depth information. In Experiments lA-1C, we measured sensitivity to surface curvature when these depth cues were available either individually or simultaneously. When the depth cues yielded comparable sensitivity to surface curvature, we found that curvature detection was easier with the cues present simultaneously, rather than individually. For 2 of the 6 subjects, this effect was stronger when the component of frontal translation of the surface was vertical, rather than horizontal. No such anisotropy was found for the 4 other subjects. If a moving object is observed binocularly, the patterns of optic flow are different on the left and right retinae. We have suggested elsewhere (Cornilleau-Pérès & Droulez, in press) that this motion disparity might be used as avisual cue for the perception of a 3-D structure. Our model consisted in deriving binocular disparity from the left and right distributions of vertical velocities, rather than from luminous intensities, as has been done in classical studies on stereoscopic vision. The model led to some predictions concerning the detection of surface curvature from motion disparity in the presence or absence of intensity-based disparity (classically termedbinocular disparity). In a second set of experiments, we attempted to test these predictions, and we failed to validate our theoretical scheme from a physiological point of view. 相似文献
53.
Two visual half-field experiments tested Moscovitch’s (1979) proposition that cerebral asymmetry does not concern the earliest perceptual stages but only later processing. Subjects were briefly shown displays that included one (Experiment 1) or two (Experiment 2) types of forms differing in size and which, according to previous evidence, might lead to opposite laterality effects. Laterality effects were assessed for correct detections and for illusory conjunctions, both in terms of raw detection scores and in terms of perceptual discriminability (dr scores). In Experiment 1, displays included either rectangles or triangles. In the first case, the target was a cross; in the second case, it was a Star of David. A hemifield x size interaction was observed both on correct detections and on associated discriminability. Yet, no such interaction was obtained for illusory conjunctions or for associated d’ scores. In Experiment 2, the two types of forms were presented simultaneously, with the small ones either inside or outside the large ones. No laterality effects were observed. Some implications of these data for both hemispheric asymmetry and feature integration issues are discussed. The results suggest that early preattentive processes of feature extraction are not lateralized, whereas some integrative mechanisms, such as Treisman’s (1988) focal attention, may operate differently in the two hemispheres. 相似文献
54.
Manuel Ruiz Ruiz Ph.D. M.D. Patricia Fernández-Baca M.D. Gloria Busby M.A. 《Journal of Contemporary Psychotherapy》1993,23(1):61-67
Paradigmatic complexes in family psychotherapy have been indicating a revolutionary change and the creation of new paradigms for the past thirty years. Starting with the application of the general systems theory and the development of those concepts that have been emerging regarding psychosomatic illnesses we discuss the epistemological confusion created, the methodological problems and the dissociation between theory and practice. We suggest a double process of investigation of the family structure using a knowledge of the basic attitudes and the development of a psychotherapy programme within the family of the psychosomatic patient. 相似文献
55.
Eric Stice Manuel Barrera Jr. Laurie Chassin 《Journal of abnormal child psychology》1993,21(6):609-629
Past research has generated inconsistent findings regarding the relation of parental control and support to adolescent problem behaviors. Using two waves of data collected 1 year apart, the current study examined the influence of parental control and support on adolescents' externalizing symptoms, alcohol use, and illicit substance use. A sample of adolescents and their parents (@#@ N =454) was studied, within which approximately half of the adolescents were at high risk because of parental alcoholism. Multipleregression analyses of crosssectional data showed a negative quadratic relation between parental control and adolescent externalizing symptomatology, and between parental control and adolescent illicit substance use. Parental control had a negative linear relation to adolescent alcohol use. Parental support showed a negative quadratic relation to adolescent illicit substance use, and negative linear relations to adolescent alcohol use and externalizing symptoms. Although longitudinally adjusted contemporaneous results were consistent with crosssectional findings, parental support and control were prospectively related only to adolescent alcohol use. The quadratic relations suggest that adolescents who receive either extreme of parental support or control are at risk for problem behaviors. 相似文献
56.
57.
F Y Doré 《Canadian journal of psychology》1990,44(3):359-370
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
58.
Medical expertise asa function of task difficulty 总被引:4,自引:0,他引:4
This paper is concerned with factors that disrupt the pattern of forward reasoning characteristic of experts with accurate performance. Two experiments are described. In the first, the performances of cardiologists, psychiatrists, and surgeons in diagnostic explanation of a clinical problem in cardiology were examined. In the second, the performances of cardiologists and endocrinologists in diagnostic explanation of clinical problems within and outside their domains of expertise were examined. The performances of researchers and practicing physicians are also compared. The results of Experiment 1 replicated earlier results regarding the relationship between forward reasoning and accurate diagnosis. There were no differences in recall as a function of expertise. Experts did not show any bias toward using specific knowledge from their own areas of expertise. The results of Experiment 2 showed that the breakdown of forward reasoning was related to the structure of the task. In particular, nonsalient cues induced some backward reasoning even in subjects with accurate diagnoses. Some differences were also found between the types of explanation used by researchers and practitioners. The practitioners referred more to clinical components in their explanations, whereas the researchers focused more on the biomedical components. 相似文献
59.
Gerardo Marín Barbara V. Marín Eliseo J. Pérez-Stable Fabio Sabogal Regina Otero-Sabogal 《American journal of community psychology》1990,18(6):847-864
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
60.
R. Harré 《国际科学哲学研究》1990,4(2):149-158
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