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41.
Transparent layer constancy   总被引:1,自引:0,他引:1  
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   
42.
Modification of Restle's theory (1970) explains the moon illusion and related phenomena on the basis of three principles: (1) The apparent sizes of objects are their perceived visual angles. (2) The apparent size of the moon is determined by the ratio of the angular extent of the moon relative to the extents subtended by objects composing the surrounding context, such as the sky and things on the ground. (3) The visual extents subtended by common objects of a constant physical size decrease systematically with increasing distance from the observer. Further development of this theory requires specification of both the components of the surrounding context and their relative importance in determining the apparent size and distance of the moon.  相似文献   
43.
This research examines the expression of positive and negative emotions under minimally social conditions. Male and female encoders were covertly videotaped while they viewed and made written ratings of their responses to a number of slides, using a list of emotion terms derived from members of the same subject pool. Results show that, even when the social nature of the situation is reduced to a minimum, the experience of some emotions is reflected on the face, and there is clear evidence for differential expression of certain positive emotions. However, the reduced social nature of the situation removes the usual female encoding advantage, supporting the suggestion that this reflects the operation of display rules. The ability to recognize the minimal expressions in this study is related to both gender and emotion type in ways that may be explained by a socialization hypothesis.I wish to thank Gill Thorpe and Eiko Mori for running the decoding subjects of this study, and Sylvie Collins, Tony Manstead, and two anonymous reviewers for comments on an earlier version of the paper.  相似文献   
44.
45.
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   
46.
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   
47.
The psychological stress reactions of 44 family medicine patients who were treated in the emergency room were examined approximately a year after the event. Patients were assessed on several psychological measures, including one for posttraumatic stress disorder (PTSD), and on their perception of how stressful the event was initially and now. Results show continuing stress reactions related to the emergency room event. Three patients endorsed symptoms indicating full PTSD and 13 appeared to have at least partial PTSD. Age appeared to be a factor in the presence of stress symptoms and in degree of perceived communication with the physician.  相似文献   
48.
The purpose of this study was to explore the role of acculturation in coping with stress among 264 Chinese-American children. The results confirmed that the subjects used a variety of coping strategies including diversion, suppression, problem solving, minimization, and retaliation and that certain coping strategies influenced the dysphoria experienced as a result of peer stress. High acculturated children used retaliation significantly more often than their low acculturated counterparts and retaliation was found to be associated with less dysphoria for the high acculturated group. In contrast, low acculturated children who utilized suppression tended to report less dysphoria. Contrary to the hypothesis that general self worth would reduce the relationship between peer stressors and dysphoria, it had no bearing on the association for either acculturated group. The hypothesis that greater perceived social competence would lessen the association between peer stressors and dysphoria also failed to be supported by the data. In fact, for the high acculturation group higher social competence was actually associated with more reported dysphoria. In general, the results suggested that the adaptiveness of particular coping strategies may be influenced by acculturation level and that social competence plays a complicated role in the stress and coping process. Implications for counsellors are discussed.  相似文献   
49.
The accreditation standards outlined in the article are used by the International Association of Counseling Services, Inc., as the basis for the formal accreditation of college and university counseling programs throughout the United States and Canada. They reflect the program elements and practice standards that are deemed essential in a counseling center that provides high-quality services to students.  相似文献   
50.
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