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This paper describes the development of the Work Environment Scale, which includes measures of perceived stressful and supportive aspects of the job milieu. This scale is used to examine stressful effects of the work environment on personal functioning and the stress-buffering value of work and family social resources among a representative community group of men and women. Work stressors had a greater impact on men, but supportive social resources provided more attenuation of such effects among men than among women. Although work stressors generally had less effect on men whose wives were employed, high stress in the women's work settings had some indirect negative consequences for their husbands. Reprint requests should be directed to the authors, Social Ecology Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University Medical School, Stanford, California 94305, U.S.A. 相似文献
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We conducted playback experiments to examine how parent tree swallows (Tachycineta bicolor) use nestling begging calls to distribute feedings to individuals within broods. In a first study, we used a paired-choice
test to determine if parents discriminated between the taped begging calls of nestlings deprived of food and those of nestlings
that had been recently fed. Our results showed that parents directed their first feeding attempt towards model nestlings near
speakers playing deprived calls significantly more often than to models near speakers playing fed calls. They also made more
feeding attempts overall to models with deprived calls. In the second study, we varied call rate and amplitude to examine
which call features parents might use to discriminate begging calls. Parents directed significantly more first feeding attempts
and more feeding attempts overall towards non-begging nestlings near speakers playing high call rates than to nestlings near
speakers playing low call rates. They did not, however, discriminate between calls differing in amplitude. Previous studies
have shown that parent birds use begging calls to regulate overall feeding rates to the brood. Our results suggest that parent
tree swallows also use begging calls when feeding individual nestlings and, in particular, prefer calls associated with increased
levels of nestling hunger.
Received: 14 February 2000 / Revised: 6 October 2000 / Accepted: 16 October 2000 相似文献
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