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101.
Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general.  相似文献   
102.
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   
103.
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   
104.
Two archival studies examined the impact of people's appearance on the status and type of civilian and military jobs they hold. Study 1 found that, although appearance was not related to job status, taller men had higher incomes. Additionally, appearance was significantly related to the type of jobs people held. Attractive women and tall men held jobs requiring traits more consistent with the attractiveness halo, while babyfaced women and short men held jobs more consistent with the babyface stereotype. These effects remained after controlling for job-relevant personality and educational variables, suggesting an unjustified bias toward people with certain appearances. Study 2 found that heavier men had lower job status, as reflected in military rank attainment. However, this relationship was eliminated when controlling for intelligence and dependability. Also, babyfaced men achieved higher status through being marginally more likely to win a military award. This unexpected effect was attributed to the contrast between heroic actions and the babyface stereotype. Finally, appearance affected the type of military experience men had. Heavier men were more likely to be in situations involving gunfire or casualties. These studies make an important contribution by extending laboratory findings to the real world, exploring the effects of appearance on job type as well as status, and providing evidence that appearance effects are not solely due to covariation with bona fide job qualifications.  相似文献   
105.
Media reports suggest that the public is becoming impatient with the homeless—that so-called “compassion fatigue” has gripped the nation. This characterization of public sentiment could have important policy consequences—restrictive measures can be justified by growing public impatience, and progressive housing policies seem infeasible within a hostile climate of opinion. But evidence to support the compassion fatigue notion is anecdotal. We examine the issue by tracking the results of public opinion polls and by reporting detailed evidence from a nationwide random-digit dial telephone survey (N=1,507) concerning knowledge attitudes and beliefs about homeless people. To be sure, the public sees homelessness as an undesirable social problem and wants something done about it. However, although the homeless are clearly stigmatized, there is little evidence to suggest that the public has lost compassion and is unwilling to support policies to help homeless people.  相似文献   
106.
Causal attributions (i.e., locus, stability, globality) and responsibility attributions (i.e., bad intent, selfish motivation, blame) were assessed in the spouses of 27 depressed psychiatric inpatients and 30 nondepressed dyads to test predictions derived from Hooley's (1987) symptom-controllability model of marital distress. Results indicated that (1) depressed patients and their spouses were less dyadically adjusted than nondepressed spouses, (2) causal and responsibility attributions about depressive behaviors predicted lower dyadic adjustment, and (3) attributions of causality mediated the relationship between group status (depressed or nondepressed) and dyadic adjustment among spouses who had higher expectations for their partner to change. Results suggest that among spouses with a high expectancy for change, depression may be a risk factor for marital distress.  相似文献   
107.
Abstract— Fourteen-year-old adolescents' behavior on a spatial-visual reasoning task was associated with self-report of their mothers' alcohol consumption during pregnancy, IS years earlier The task was arranged so that it was possible to evaluate the examinees' tendency to respond rapidly and less accurately, or slowly and more accurately The greater the mother's reported drinking, the faster and less accurately the adolescent responded The decrement in visual-spatial reasoning related to alcohol appears to be linked to a tendency toward impulsive responding  相似文献   
108.
An advantage of first mention—that is, faster access to participants mentioned first in a sentence—has previously been demonstrated only in English. We report three experiments demonstrating that the advantage of first mention occurs also in Spanish sentences, regardless of whether the first-mentioned participants are syntactic subjects, and regardless, too, of whether they are proper names or inanimate objects. Because greater word-order flexibility is allowed in Spanish than in English (e.g., nonpassive object-verb-subject constructions exist in Spanish), these findings provide additional evidence that the advantage of first mention is a general cognitive phenomenon.  相似文献   
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