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191.
In recent years the developmental implications of menarche have garnered particular attention. Investigators have determined that this developmental event tends to affect three significant domains of the adolescent girl's function: psychological status, relationships with peers, and role in the family. This paper explores these issues and introduces a new technique, referred to as previewing, that may help the teenage girl acclimate to the status of sexual maturity. Derived from the early life interactions of caregiver and infant, previewing promotes representational skills and enhances self-esteem as the adolescent confronts developmental challenges.  相似文献   
192.
In the mid 1980s it was apparent that the need for organ donors exceeded those willing to donate. Some University of Pittsburgh Medical Center (UPMC) physicians initiated discussion of possible new organ donor categories including individuals pronounced dead by traditional cardiac criteria. However, they reached no conclusion and dropped the discussion. In the late 1980s and the early 1990s, four cases arose in which dying patients or their families requested organ donation following the elective removal of mechanical ventilation. Controversy surrounding these cases precipitated open discussion of the use of organ donors pronounced dead on the basis of cardiac criteria. Prolonged deliberations by many committees in the absence of precedent ultimately resulted in what is, to our knowledge, the country's first policy for organ donation following elective removal of life support. The policy is intricate and conservative. Care was taken to include as many interested parties as possible in an effort to achieve representative and broad based support. This paper describes the development of the UPMC policy on non-heart-beating organ donation.  相似文献   
193.
Previous studies of infants’ ability to integrate and to utilize relative motion as information for form in the absence of structural cues have primarily involved motions that are uniform in rate, direction, and path within the form to be constructed. In the present study, we examined infants’ ability to integrate relative motion information from motions that are nonuniform along these dimensions, and from this integrative process to construct a coherently rotating two-dimensional form. Infants’ ability to integrate nonuniform motion was measured with regard to their ability to discriminate the rotating form from a noncoherent control display containing the same absolute motions. The results showed that discrimination of the coherent and incoherent displays was not demonstrated until 7 months of age. Two additional experiments were conducted to rule out the possibility that this discrimination was based on the detection of local regions of coherence, rather than the perception of the global rotating form. In both experiments, the results did not support discrimination based exclusively on local cues alone. From the combined results of all three experiments, we conclude that infants demonstrate the capacity to integrate the information contained within nonuniform trajectories into a coherent structure by 7 months of age.  相似文献   
194.
The concept of systemic quantization of behavior was used to study the interaction between dominant motivation and reinforcement on brain neurons. Feeding and escape were used as experimental models. Results showed that feeding and escape motivations are based on the mechanisms of ascending activating influences of lateral or ventromedial hypothalamic centers, respectively, on cortical neurons. Feeding and escape motivations evoked by electrical stimulation of hypothalamus, or the ones occurring naturally, modify the responses of single neurons of sensorimotor and insular cortex to sensory stimuli, to microiontophoretic application of neurotransmitters and neuropeptides, and especially to reinforcement. Dominant motivations are reflected in the burst-like activity and in a specific pattern of interpulse intervals of single units in various brain structures. Reinforcement transforms this activity into a regular pattern and also changes the neuronal responses of hypothalamic feeding and escape centers, to electrical stimulation and to microiontophoretic application of oligopeptides. Specific patterns of the unit responses to conditioned stimuli in the course of consecutive reinforcement was determined. After several instances of reinforcement, especially after repetitive reinforcement, the brain neurons influenced by the dominant motivation begin to produce specific protein molecules that are important for organization of an appropriate type of behavior. This process can be blocked by protein synthesis inhibitors.  相似文献   
195.
196.
A study was conducted with 225 college students to examine the effects of three organizational and policy variables on the perceived fairness and invasiveness of drug-testing practices. Specifically, the effects of warning type (no warning vs. advance warning), consequence of a positive drug test (termination vs. rehabilitation), and safety sensitivity of the job (safety sensitive vs. safety nonsensitive) were examined. Results suggested that specific features of the policy, as well as type of job under consideration, affected perceived invasiveness and fairness of drug testing. In general, testing was seen as more appropriate for safety-sensitive jobs, that is, those in which drug-impaired performance presented a high degree of danger for individuals. Although rehabilitation was perceived as more fair than termination, when safety was an issue, termination was viewed as a justifiable response by the company. Implications for organizational drug-testing policies are discussed.  相似文献   
197.
Throughout history dreams have been primarily the province of religion. People in many cultures have looked to dreams as sources of spiritual insight and divine revelation. The relationship between traditional religious views of dreams and modern psychological views of dreams has long interested psychologists of religion—for dreams are a uniquely fertile subject for comparing religious and psychological understandings of human experience. In recent years there have been many revolutionary discoveries in dream research, discoveries that have taken us far beyond the seminal works of Freud, Jung, and the early sleep laboratory researchers. This essay describes the work of three leading contemporary dream researchers (neurophysiologist J. Allan Hobson, psychologist Stephen LaBerge, and anthropologist Barbara Tedlock) and evaluates the implications of their findings for our understanding of the religious dimensions of dreams. The essay concludes with some reflections on the valuable role of dream study in the psychology of religion. The primary claim is that recent dream research can make important contributions to current psychology of religion discussions about such issues as interdisciplinary inquiry, hermeneutics, the cross-cultural study of religious experience, the cultural and religious context of modern psychology, and the practical concerns of pastoral counselors.This essay is based on a paper presented on November 25 at the 1991 Annual Meeting of the American Academy of Religion, Kansas City, Missouri.  相似文献   
198.
Twenty-six infants, 3 to 23 months old, were trained on fixed-interval schedules ranging from 10 s to 80 s. The operant response was touching an illuminated location on a touch-sensitive screen, and 20 s of cartoon presentation was the reinforcer. The subjects were also trained in a six-phase self-control procedure in which the critical phases involved choice between 20 s of cartoon available after a 0.5-s delay (impulsive choice) and 40 s of cartoon delayed for 40 s (self-controlled choice). All the youngest children (3 to 5 months) showed long postreinforcement pauses on the fixed-interval schedule, with most intervals involving the emission of a single, reinforced, response, and all made self-controlled choices. Older subjects (9 to 23 months) either produced the same pattern as the younger ones on the fixed-interval schedule (classified as pause-sensitive subjects) or produced short pauses and higher steady response rates (classified as pause-insensitive subjects). All pause-sensitive subjects made self-controlled choices in the self-control condition, and all pause-insensitive subjects made impulsive ones.  相似文献   
199.
The Gender Role Journey concept was developed to help women and men explore their gender role changes and transitions. A 34-item Gender Role Journey Measure (GRJM) was conceptualized and developed through empirical methods. The construct validity of the five phases of the gender role journey is assessed. The GRJM and the Personal Attributes Questionnaire (PAQ) were given to a sample of women and men (N=878). The sample was predominantly Caucasian from a mixed ethnic background. Principle factor analysis indicated three meaningful factors: Acceptance of Traditional Gender Roles; Gender Role Ambivalence, Confusion, Anger, and Fear; and Personal-Professional Activism. Moderately high test-retest and internal consistency reliabilities were found for each of the factors. Gender differences and gender by PAQ interactions were found for all three of the factors of the GRJM. Implications for future research, teaching, and workshops are suggested.This article was presented at the 99th convention of the American Psychological Association, San Francisco, California, August 1991. It was supported by a grant from the Research Foundation of the University of Connecticut, Storrs, Connecticut.  相似文献   
200.
V D Gifford  M M Dean 《Adolescence》1990,25(100):799-802
The purpose of this study was to determine the type of school organization that most benefited ninth-grade students. Results indicated that ninth graders in the junior high school setting participated significantly more in extracurricular activities and achieved significantly higher academically than did ninth graders in the senior high school setting.  相似文献   
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