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991.
Six hens were exposed to several concurrent (second-order) variable-interval schedules in which the response requirements on the alternatives were varied. The response requirements were one key peck versus five key pecks, one key peck versus one door push, and five key pecks versus one door push. Response- and time-allocation ratios undermatched the obtained reinforcement ratios but were well described by the generalized matching law. Time and response bias estimates from two pairs of response requirements were used to predict bias in the third pairing. The predicted values were close to those obtained; this result supports the notion that both numerically and topographically different responses act as constant sources of bias within the generalized matching law. The differences between the response and time biases could be accounted for by the different times needed to complete each response requirement. The results also suggest that the door push is a useful operant for research with domestic hens.  相似文献   
992.
In this study, we explored differences in personality and daily life experiences of traumatized (n= 26) versus nontraumatized (n= 30) college students. Study participants completed a variety of personality measures as well as a 28–day experience sampling study assessing daily activities, emotions, and physical health. Although not differing on general demographics, traumatized individuals reported more trait anxiety and lower self–esteem than nontraumatized individuals. They scored higher on Neuroticism, were more introverted, and were less emotionally stable than nontraumatized participants. Traumatized individuals also reported more cognitive disturbances, emotional blunting, and interpersonal withdrawal. They did not report being more depressed, but did endorse cognitive styles associated with heightened risk for depression. Earlier age of trauma was associated with more pathological outcomes: lower self–esteem and psychological well–being, more anxiety, more pessimism, and emotional constriction of positive mood. We compare this symptom profile to that of posttraumatic stress disorder.  相似文献   
993.
Both theoretical arguments and laboratory evidence indicate that society awards earned dignity (worth) to persons perceived as voluntarily performing praiseworthy behaviors. Laboratory research, as well as common observation, indicates also that society accords an intrinsic dignity unconditionally to all people. On a questionnaire given in class, college students reported increased dignity earned by the Russians from their praiseworthy (i.e., embracing freedom) and voluntary rejection of the attempted coup in 1991. The questionnaire also revealed a general belief in intrinsic dignity. External evidence for earned dignity is shown by increased international support for the Russians after rejection of the coup. This convergence of laboratory and external data validates the laboratory techniques for studying social perception of human dignity.  相似文献   
994.
995.
The present study sought to determine the role that knowledge of abortion information and various demographic variables play in discriminating between those who approve and those who disapprove of abortion. Four hundred and fifty-four college students completed the Abortion Knowledge Test, constructed by the researchers, as well as an abortion attitudes questionnaire which asked subjects to indicate their degree of approval or disapproval of abortion in the case of 7 different scenarios. Attitudes toward abortion were significantly predicted by knowledge of abortion-related information above and beyond the significant influence of degree of religiosity, religion, and age. No significant gender differences were found. Respondents who indicated approval of abortion scored significantly higher on the Abortion Knowledge Test and tended to be older, less religious, and non-Catholic compared to those who disapproved of abortion.  相似文献   
996.
Few studies have examined the correlational and structural relationships between measures of hostility that may predict coronary heart disease. Using data from a population-based study (N= 2,682), we examined the factor structure among the five subscales from Siegel's (1986) Multi-dimensional Anger Inventory, the three subscales from Spielberger et al.'s (1985) anger expression scales, a Cook-Medley (Cook & Madley, 1954) hostility subscale that measures cynicism, and items measuring hostility from four scales that assess Type A behavior. Eight separate factors were identified: hostile anger expression, perceived control over the expression of one's anger, frequency of anger, ease of anger provocation, brooding, hostile outlook, cynicism, and sullenness. These results suggest that the structure of hostility measures is more complex than previous factor analyses have suggested. Our findings point to the dangers in assuming that a factor structure can be generalized beyond the data on which it is based to provide theoretical statements about psychological structure. The new scales appear to be valid because they correlate with demographic variables and indicators of social support in the expected directions.  相似文献   
997.
998.
999.
The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.  相似文献   
1000.
Based on extensive formative research in the three Eastern Caribbean countries of St. Lucia, St. Vincent and the Grenadines, and Grenada (Fishbein, Middlestadt, & Trafimow, 1993; Fishbein, Trafimow, et al., 1993), a three-nation, mass media, condom use campaign was developed. In order to assess the impact of the campaign, a follow-up survey was conducted in St. Vincent and the Grenadines. This paper examines the effectiveness of the campaign by comparing responses on this survey by respondents who were or were not exposed to the campaign. A statistically significant impact of exposure to the campaign was obtained, indicating that a well-designed, empirically based, mass media campaign can be an effective tool in the battle to prevent the spread of AIDS.  相似文献   
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