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811.
Estimate the amount of frequency variation that affected individual and species recognition by song in territorial male field sparrows with field playbacks of neighbors' songs lowered in frequency in 6 increments between 324 and 1296 Hz. Males gave strong responses to neighbors' songs that had been lowered by about 400 Hz, which is about 11% of the mean midfrequency in field sparrow song. Territorial responses were eliminated when neighbors' songs were lowered by more than about 900 Hz. Thus, there is a fairly narrow range of frequencies within which field sparrow songs can vary while functioning in communication. Ss' responses appear to be constrained by the normal range of song frequency variation within the species, but the range of variability within songs of individuals did not influence the degree of frequency shift required to render neighbors' songs unfamiliar.  相似文献   
812.
813.
Prior to assuming the upright crouching posture over their pups during nursing bouts, lactating rats typically engage in several oral behaviors, including nuzzling, licking and rearranging pups. By acutely depriving dams of various aspects of perioral stimulation from pups (with anesthesia of the mystacial pads or of the tongue, with mouth suturing, or with muzzling), we found the following: (1) Distal stimulation from pups maintains proximity-seeking behavior, but is insufficient to stimulate nursing behavior. (2) Lack of tongue feedback decreases pup licking and hastens the onset of crouching. (3) Snout, but not tongue, contact with pups is required for hovering over them. (4) The position of the dam while hovering over her litter enables the pups to gain access to her ventrum, thereby provoking her upright, crouching posture. (5) Older pups are capable of bypassing the dam's perioral attentions and stimulating crouching directly by burrowing under the dam's ventrum.  相似文献   
814.
The physiological effects of racism, as a stressor, were examined as they related to blood pressure (BP) and anger experiences in Black college students. Current research has failed to consider the stressful effects of racism as a factor contributing to the higher incidence of essential hypertension among Blacks. Twenty-seven Black college students viewed three excerpts showing racist situations involving Blacks; anger-provoking, nonracist situations; and neutral situations. After each scene, BP was taken, and a mood checklist was administered. The Framingham Anger Scale and the Anger Expression Scale were administered. Analyses revealed that BP significantly increased during the presentation of racist stimuli but not of anger-provoking or neutral stimuli. Self-reports of state anger, as measured by the mood checklist, were significant for both the anger-provoking and racist stimuli. BP scores were significantly correlated to the two trait anger measures. Exposure to racist stimuli was associated with BP increases among Blacks. Such cumulative exposure to racism may have important implications for the etiology of essential hypertension.  相似文献   
815.
The study was designed to examine the influence of significant others (mothers, fathers, and male and female peers) on continuing involvement in sport by adolescent females. Survey data were collected from 376 girls using a forced-choice, self-administered questionnaire. Maintenance of involvement was measured by the proportion of possible years in which the respondents were involved in physical activity within each of three participation contexts (intramural, interschool, and community sport). Several indicators of significant other influence were used. The degree to which involvement in physical activity is maintained is positively related to the source, amount and type of influence received from significant others, and varied by the participation context. Overall, the socializing influence of significant others was able to account for 11% of the variance in intramural activity, 20% of the variance in interschool sport, and 10% of the variance in community-based activity.This study was funded by a grant from Fitness Canada.  相似文献   
816.
817.
Douthitt  Robin A. 《Sex roles》1989,20(11-12):693-704

The purpose of this paper was to examine more recent time-use data regarding the division of labor in the home and compare those findings with that of previously reported data. A 1981 national sample of married Canadian men and women's time use was examined. Generalized least squares regression was employed to examine and predict time use by married men and women as a function of spouse's labor force status, number of children, age of youngest child, and day of the week data were collected. As compared to previous studies, results indicate that over time married women have reduced the amount of time spent in meal preparation while increasing time spent with children. Men increased the amount of time spent in food preparation and child care, although their participation appeared limited primarily to weekend days and invariant to wife's labor force participation.

  相似文献   
818.
This paper addresses the use of the weekly written summary with patients in group psychotherapy. In an effort to stimulate group process and effect cotherapist communication, the authors instituted this group recording in an ongoing psychodynamically oriented mixed adult group. While the utilization of this device did, in fact, stimulate the group process and became an important part of the group's life, the therapists additionally saw significant effects upon their working alliance. These included increased focused dialogue upon group dynamics, more purposeful planning for group interventions, and heightened awareness of the significance of interventions in the group.Ms. Bosman-Clark is formerly Clinical Instructor, Department of Psychiatry, Baylor College of Medicine.  相似文献   
819.
Brief group psychotherapy as a method of treating psychological aftereffects of retirement is still in its infancy. It is therefore still possible to outline the whole field in overview. This paper examines the dynamics of aging and the relevant literature, discusses the conceptual issues involved, and describes techniques employed with this specific population. The typical cluster of complaints is portrayed, the psychological stressors associated with retirement are analyzed, and the various group-therapeutic modalities developed to counteract them are described. Furthermore, the rationale, process and characteristics of short-term group psychotherapy in the treatment of adjustment difficulties to retirement are reviewed. The clinical application of this approach, the therapist's particular roles and the therapeutic impact of this method are delineated.He would like to thank his co-therapist, Mrs. Sophie Bielawski, Reg. O.T., for her support and helpful observations and Drs. J. Regan and E. Sunday for their advice on methodolody.  相似文献   
820.
This study examined the ability of both an overt integrity test and a personality-based measure of delinquency to predict on-the-job theft and counterproductivity. A heterogeneous sample of 105 employees anonymously completed both tests and a criterion checklist that included a 9-item theft subscale and a 12-item counterproductivity subscale. Results indicated that the overt integrity test was a superior predictor of both on-the-job theft and drug abuse compared to the personality-based measure. The overt integrity test was also a slightly better predictor of general counterproductivity. These findings and their implications are discussed.  相似文献   
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