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871.
Task dynamics corresponding to rhythmic movements emerge from interactions among dynamical resources composed of the musculature, the link segments, and the nervous and circulatory systems. This article investigated whether perturbations of interlimb coordination might be effect over circulatory and nervous elements. Stiffness of wrist-pendulums oscillated at a common tempo and at 180 degrees relative phase was perturbed through the use of tonic activity about an ankle. Left and right stiffnesses, the common period, and the phase relation all changed. Stiffnesses increased with ankle torque in proportion to the wrist's inertial load. Despite different changes in stiffness at the two wrists, isochrony was preserved. The stability was shown to be consistent with the proportionality of changes in stiffness to the inertial loads. The phase departed from antiphase in proportion to the asymmetry of inertial loads. The size of departures decreased with increasing ankle torque. An account was developed in terms of muscular, circulatory, and nervous functions.  相似文献   
872.
873.
The authors propose a diagnostic for distinguishing between serial and parallel processing in visual search; it is based on testing for subadditive effects of a within-trial visual quality manipulation on target-absent trials. It was evaluated in 2 experiments wherein parallel and serial processing might be expected on the basis of previous work and was then applied to a more uncertain situation in a third experiment. The diagnostic indicates parallel processing of stimuli that differ from each other on a featural basis (Xs and Os) and canonical letters that differ in line arrangement (Ts and Ls) but serial processing when Ts and Ls are randomly rotated. These results form a coherent pattern that is understandable in terms of the literature on visual search, and thus they suggest that the diagnostic may be a useful addition to the methodology used to distinguish between serial and parallel processes.  相似文献   
874.
The presence of other Aplysia in the environment increases the time spent feeding. This finding is consistent with the hypothesis that a common arousal mechanism modulates feeding and reproductive behaviors. The arousal level is presumably increased by pheromones released by additional animals.  相似文献   
875.
Gender differences in health-related quality of life   总被引:1,自引:0,他引:1  
In 1986 the life expectancy at birth was 71.3 years for males and 78.3 years for females--providing a 7-year advantage for women. Although women live longer, it has been reported that they paradoxically experience more physical and psychological illnesses. In this article, we estimate the expected well-years or quality-adjusted life years for men and women in the general population. The data were obtained in a random sample of 1,034 residents of San Diego. The well-life expectancy uses standard life expectancies with adjustments for quality of life. The well-life expectancy for men was 59.8 years; for women, it was 62.7 years. Thus, the quality adjustment had significantly more impact on women (15.6 years) than on men (11.5 years). Age-specific estimates of health-related quality of life suggested a male advantage before age 45 and a female advantage after age 45. The benefits of well-years of life as a public health statistic are discussed.  相似文献   
876.
This study examines the effect of perceptions of mothers' and fathers' parenting behavior on their college-aged daughter's gender role development. Unlike in previous studies, in this analysis we consider both the gender role traits of young females (their instrumentality and expressiveness) and their gender role preferences (modernity vs. traditionalism) simultaneously. Three alternative empirical models are tested with data from 163 randomly selected college-aged females using analysis of covariance structures in LISREL VII. Findings substantiated the hypothesis that perceptions of earlier parenting behavior exert a substantial influence on gender role developments of children, particularly regarding mothers' influence on the instrumentality and expressiveness of their daughters. Mothers' parenting, measured along the dimensions of encouragement and control, was generally more strongly related to their daughters' gender role traits than was fathers'. Little influence of parenting behavior on daughters' gender role preferences was found.The authors wish to acknowledge Dr. Hyman Rodman for his comments on earlier drafts of this paper.  相似文献   
877.
Even though in Italy, as in the majority of Mediterranean countries, the increase in suicide rates is not among the highest in Europe, between 1969 and 1989 it showed a sharp upswing (+43% among males and +31% among females). In terms of geographical differences, the regions with the highest suicide rate are the northern ones (up to twice the national average). The age groups with the highest suicide risk are those over 74 years (in 1989 the rate among males over 65 was the highest of all: 31.3 per 100,000). The differences in the between-sexes distribution show that among females over 65 years old the suicide rate rose by 70% between 1974 and 1989, versus 77% for males of the same age. The preliminary epidemiological results of one of two Italian centers are presented. These centers are collaborating with the WHO/EURO Multicenter Study on Parasuicide; parasuicide rates are higher for females than for males (55.9 per 100,000, as against 38.1 for males), while the age group at highest risk is seen to be young women (15-24 years), with a specific rate of 115.6.  相似文献   
878.
This paper, which was presented at the Postgratuate Center for Mental Health, New York, February 10, 1990, is a much abbreviated version of Playfulness in the Psychoanalytic Relationship,Contemporary Psychoanalysis, 26(1), 74–95, 1990.  相似文献   
879.
Very few behavioral patterns generalize across human and nonhuman species. We describe washing, drying, and anointing sequences in humans (Homo sapiens) that may have analogies with other species. The rank ordering of washing, drying, and anointing body parts was obtained over 3 successive days for 37 men and 60 women. Variation in rank ordering of body parts was nonrandom, and a cephalocaudal progression was evident for each behavior. Reliability of the behaviors as well as the correlations across rankings were highly significant, which indicates a generalized cephalocaudal progression for all 3 behaviors. Women's anointing was most variable, which suggests a more specific function. The cephalocaudal action pattern described for humans is similar to that for Mongolian gerbils and laboratory rats. Cross-species functions, such as these, may add to our understanding of common developmental and learning processes.  相似文献   
880.
Data from a sample of clinicians are examined to study the relationship of the lower socio-economic client and therapist. Therapist practice variables are regressed on variables measuring client income and contrasting client's use of Medicaid with the use of private insurance or out-of-pocket funds. It is found that therapist practice variables can predict a significant proportion of the variance of these criterion variables. These relationships and their implications for the therapeutic needs of indigent clients with less severely impaired conditions are discussed.  相似文献   
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