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991.
Most knowledge of parent-offspring relations in mammals is derived from studies of mother-infant interactions. Male parental care has been less well studied. We explored maternal and paternal behavior of the California mouse, Peromyscus californicus. Six pairs of parents and their young were videotaped continuously for 12 hours/day, on alternate days from Days 1 to 31 postpartum. Males exhibit all parental activities and to the same extent as displayed by mothers, except lactation. Male parental behavior begins on the day of birth. Mothers and fathers spend substantial and equivalent amounts of time in the nest and in physical contact with pups throughout lactation. Males devote more time than females to licking pups, although females engage in more pup anogenital licking. Mothers nurse for at least 4 weeks, and fathers and mothers both build nests and carry young. The biparental care system of Peromyscus californicus affords an opportunity to develop a broader, more complete view of parent-offspring relations.  相似文献   
992.
Several theories have been presented that predict differences between women and men in attitudes toward the environment due to differences in sex roles. Research on which these theories can be tested has tended to examine general environmental concern, and the results have generally been weak and inconclusive. Using an approach suggested in the literature, this study examines sex differences in concern and knowledge, using multi-item scales for each, about one environmental issue — acid rain. The results contradict the theories being tested, however: if there is a sex difference, men are found to be more concerned and knowledgeable about the environmental problem.  相似文献   
993.
Twenty elderly subjects (70-90 years old) and 20 young control subjects (18-24 years old) underwent three kinds of olfactory testing: absolute thresholds to three odorants (d-limonene, iso-amyl butyrate, benzaldehyde), magnitude matching of these odorants to salt tastes, and odor identification of 30 common substances. For all three odorants elderly subjects' mean threshold significantly exceeded that of the young by about ninefold for d-limonene, about threefold for benzaldehyde, and about twofold for iso-amyl butyrate. These threshold differences predict approximate concentration differences necessary to arouse the same estimated odor strength above the threshold for the elderly and the young. Young subjects also scored better than the elderly in odor identification, even when subjects were given four alternatives from which to select the correct label. Unimpaired olfactory functioning is uncommon in the elderly; correlational tests show that as a group the young have better olfactory ability and show more interindividual uniformity.  相似文献   
994.
Affect, personality, and facial expressive characteristics of older people   总被引:1,自引:0,他引:1  
This study explored the relationship between emotion-based personality traits and expressive patterns in older subjects. Specifically, the study sought to demonstrate (a) that individuals have emotion expression biases, as revealed by structural and dynamic properties of the face, and (b) that there is a link between facial characteristics (as indexed by the judgments of trained and naive raters) and personality traits. An encoding/decoding paradigm was used; 30 adult, naive judges rated five emotion-pose photographs for each of 14 older subjects who had also completed a personality trait measure. Results indicated that individuals vary in their ability to accurately encode emotion states and that these patterns are linked to personality traits in an affect-specific way. The results are discussed within the framework of Darwinian theory and Plutchik's model of personality.  相似文献   
995.
Elderly subjects were 41% less accurate than young subjects in localizing a point in the frontal plane. The decline could be ascribed neither to an age difference in image formation or skill acquisition nor to a difference in motivational level or trace retention. Evidently the "ambient" or "transient" visual system is compromised at an elementary level. Reasons why this deficit may not be compounded at more complex levels of spatial processing are suggested.  相似文献   
996.
997.
The purpose of this article is to encourage behavior analysts to expand their domain of interest and application to include the "social/political" contingencies that are developed and implemented by policymakers and lawmakers. Using the Vermont juvenile justice system as a prototype, examples are provided that focus on the tertiary, secondary, and primary prevention of delinquent behavior.  相似文献   
998.
999.
The authors demonstrate the complexities and processes involved in constructing a screening test for posttraumatic stress disorder (PTSD). Discussion includes item development, field testing, and preliminary results.  相似文献   
1000.
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