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971.
This intervention sought to improve first-year college students' attitudes about rape. The Elaboration Likelihood Model (ELM) was used to examine men and women's attitude change processes. Both quantitative and qualitative methodologies were used to examine how men and women construed rape prevention messages. Results indicated numerous sex differences in the ways in which men and women experienced and changed during and after the rape prevention intervention. Women seemed to use more central-route attitude change processes and showed more lasting change from the intervention at 2-month follow-up, whereas men seemed to attend more to peripheral cues of the speaker and demonstrated more transient attitude change.  相似文献   
972.
The measurement of the adrenocortical hormones, Cortisol and corticosterone, m blood plasma has previously best been done by procedures employing varying degrees of purification of the hormone, followed by photometric or fluorimetric quantitation. These methods have been relatively difficult or laborious, particularly in the case of the procedures that most specifically measure the hormoneof intent. These limitations are considerably overcome by new assays for Cortisol and corticosterone based on the principle of competitive protein-binding of the steroids in the presence of radioactively labeled steroid of the same molecular species. These methods are described and data on the specificity of such a method for corticosterone are presented and compared with one of the better fluorimetric assays.  相似文献   
973.
The key-pecking of a pigeon was reinforced with grain on an 18-min second-order schedule. During the 18 min, a key peck which completed a 3-min fixed interval produced a stimulus of 0.5-sec duration. The first 3-min fixed interval completed after 18 min resulted in primary reinforcement. Behavior characteristic of fixed-interval schedules was produced on both the 3-min components and the 18-min schedule. This performance was shown to be enhanced whenever the 0.5-sec stimulus was also presented before the presentation of grain.  相似文献   
974.
Social reasoning and spatial paralogic   总被引:12,自引:0,他引:12  
  相似文献   
975.
976.
After reviewing the literature on the relationship between sex education and sexual and contraceptive behavior, the National Research Council (1987) recently concluded that the existing evaluation of the effects of sex education on sexual and contraceptive practice is helpful but not sufficient. 1 possible explanation for the different results obtained are the diverse sociodemographic characteristics of the sample(s) of teens under consideration. Another aspect which might account for the differences seen in the literature focuses on the areas covered in the course. In Mexico, no studies have been undertaken which deal with the relationship between sex education and sexual and contraceptive behaviors. A study carried out with 392 adolescent females ages 16-17 of lower and middle lower socioeconomic status showed that merely attending a sex education course did not affect the initiation or continuation of sexual activity, contraceptive behavior, or even the perception of accessibility to contraception. Providing information on sexuality, partner relationships, and where contraception can be obtained does not appear to have any effect on sexual activity. Receiving information on pregnancy prevention and obtaining contraceptives was found to be related to contraceptive use. Although less dramatic, information about partner relationships and sexuality produced increases in contraceptive use.  相似文献   
977.
Theoretically, optic flow, an important source of information for the perception of locomotion and three-dimensional structure of the environment, is described in terms of divergence, curl, and shear components. We measured how the detection of the type of flow field depends on directional information. We manipulated the local directions by rotating them through an angle x relative to the original direction (i.e., the direction of motion at that locus in an unaltered flow field). The results of the first experiments showed that divergence, curl, and shear can be detected even if the directional range of the individual motion vectors is as broad as 180 degrees. Subsequent experiments revealed that the detection of the geometric components of the optic flow field is merely based on the integration of a few (10% of vectors) local directions correctly (within 10 degrees of original direction) specifying the type of flow field. Other directions are irrelevant to this process. This is actually what one would expect if the optic flow is analyzed by special purpose mechanisms that detect and process the geometric components on the basis of the integration of motion information. The results indicate that as far as they integrate motion information, detectors for divergence, curl, and shear operate in a similar manner. Implications of the results for modeling such mechanisms are discussed.  相似文献   
978.
Occlusion cues defining a contour in a 2-D stimulus pattern were shown to contribute to the accuracy of orientation judgments of that contour. The stimulus pattern was altered so that the occlusion cues became ambiguous, by introducing a textured background suggesting transparency of the stimulus pattern. Orientation judgments then became significantly less accurate. This finding shows that occlusion cues in 2-D patterns can be behaviorally relevant, in addition to generating the subjective percept commonly known as an illusory contour. The disruptive effect of the textured background on orientation judgments remained when no texture elements were present in the vicinity of the contour. This suggests that the generation of occlusion-defined contours relies as much on an evaluation of the surfaces at either side of the contour as being opaque as it does on local encoding of occlusion cues close to the contour. Finally, orientation sensitivity measured with contours defined by other than occlusion cues was not altered after the introduction of a textured background.  相似文献   
979.
119 female prostitutes were interviewed over the period July 1990-March 1991 about their sex behavior and condom use, their working attitude, and perception of risk in an attempt to combine qualitative and quantitative research methods to gain insight into the determinants of condom use in prostitution by putting high or low risk taking behavior into context. The participants were recruited from different regions of the Netherlands, of mean age 29.8 years, and had been working in the field for an average 6.8 years. Most of the 28% of participants who did not have Dutch nationality were from Germany or Latin America. Health locus of control and attributions concerning an unpleasant proceeding of client contacts were assessed by means of item lists. Prostitutes were identified as either consistent condom users, selective risk takers, or risk takers. Consistent condom users used condoms on all occasions, selective risk takers used condoms for vaginal sex with all but a few selected clients, and risk takers seeing no possibility of consistently getting clients to use a condom for vaginal sex used condoms the least frequently. 78% were consistent users, 11% were selective risk takers, and 11% were risk takers. Protection behavior was found to be linked to working attitude. Condom use is most likely among women with a moderately positive, yet businesslike, working attitude, and least likely among those with a negative working attitude and when there is no positive identification with the professional group. It appears that health locus of control is of no influence on protection style, but risk takers attribute an unpleasant proceeding of client contacts significantly more to powerlessness and helplessness. The authors conclude that the objective situation of women influences condom use at least as strongly as subjective motivations.  相似文献   
980.
This article describes the development and testing of a new 97-item self-report instrument assessing the frequency and intensity of 11 developmentally related domains of concerns of middle-aged men. These include relationships (child, parents, wife, friends), job, health, sex, leisure, death, pressures of time, and self-reflection. The psychometric properties of the instrument, as well as potential uses, are discussed.  相似文献   
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