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201.
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   
202.
Does the introduction of additional contours in a display sequence (an operation known to reduce the strength of suppression in metacontrast) also reduce suppression of visible persistence? In three experiments, duration of visible persistence was estimated by a method in which successful performance depends on the temporal integration of a pattern whose elements are displayed in two successive frames. In this procedure, the arrival of the trailing frame is known to exert a suppressive influence on the visible persistence of the leading frame. Embedding the elements of the leading frame within additional contours (a line grid) reduced the degree of suppression exerted by the trailing frame. This did not occur when the grid was part of the trailing display. We conclude that suppression of visible persistence and metacontrast masking belong to the same class of events.  相似文献   
203.
Findings concerning the effectiveness of stimuli from various conditioning procedures in blocking conditioned excitation and occasion-setting functions of an added stimulus in a serial feature-postive discrimination training procedure (LoLordo & Ross, 1987; Ross & LoLordo, 1986, 1987) are retracted. Videotapes on which the published data were based were rescored by 2-5 people, most of whom were uninformed about group memberships of the subjects. In no case did the rescoring confirm any of the orginal findings of blocking. Possible factors contributing to the discrepancies are discussed. The experiments should be repeated with feature stimuli that are less similar to each other and with several scorers, at least one of whom is unaware of the group assignment of the subjects.  相似文献   
204.
The perception of transparency is highly dependent on luminance and perceived depth. An image region is seen as transparent if it is of intermediate luminance relative to adjacent image regions, and if it is perceived in front of another region and has a boundary which provides information that an object is visible through this region. Yet, transparency is not just the passive end-product of these required conditions. If perceived transparency is triggered, a number of seemingly more elemental perceptual primitives such as color, contour, and depth can be radically altered. Thus, with the perception of transparency, neon color spreading becomes apparent, depth changes, stereoscopic depth capture can be eliminated, and otherwise robust subjective contours can be abolished. In addition, we show that transparency is not coupled strongly to real-world chromatic constraints since combinations of luminance and color which would be unlikely to arise in real-world scenes still give rise to the perception of transparency. Rather than seeing transparency as a perceptual end-point, determined by seemingly more primitive processes, we interpret perceived transparency as much a 'cause', as an 'effect'. We speculate that the anatomical substrate for such mutual interaction may lie in cortical feed-forward connections which maintain modular segregation and cortical feedback connections which do not.  相似文献   
205.
Human interaction and communication involve space in multiple ways. This paper examines the spatial and interactional order of a covertly video-taped police interrogation. When the participants enter the interrogation room and become engaged in the interrogation process, the room itself is a constraint and a resource for interaction. While interacting within a built environment, the participants appropriate their material surroundings in ways that constitute a spatial order and make possible certain arguments. This paper examines how the physical structure of the interrogation room is differentially appropriated, used, and filled in by the participants'; territorial and postural manoeuvers over the course of their interaction; and how the spatial structures thus created by the bodily appropriation of the physical locale are subsequently formulated by talk and thereby used as a metaphorical resource to frame the participants' situated experience. Through this embedded process, the interrogators move the suspect toward confession.  相似文献   
206.
Visual analogue scales (VASs) are one of the most widely used self-report measures of clinical pain. This article reviews the empirical literature on linear analogue self-assessment (LASA) and critically examines the features that appear to have made it such an attractive measurement option in pain assessment. It is concluded that analogue scaling does not withstand critical scrutiny as a primary measure of either pain intensity or pain affect and that, in most circumstances, the overall clinical utility of VASs is inferior to that of more structured pain indices.  相似文献   
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Neural structures involved in aggression were incorporated into a model on the basis of neuro-anatomical data. A software program written in Smalltalk, the Brain Structure Simulator (Seguin, 1994) was used to simulate the effects of activity levels of different brain structures. Relationships among brain structures were then tested by changing activity levels of key structures. Results were consistent with research reports on the brain basis of aggression (Albert, Walsh, & Jonik, 1993; Pontius, 1984).  相似文献   
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