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21.
Edmond A. Murphy Kenneth R. Berger Joseph E. Trojak E. Manuel Rosell 《Theoretical medicine and bioethics》1989,10(4):355-365
Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated. 相似文献
22.
This article reports an experiment to investigate the idea that time-of-day differences in memory for text are related to
type of text processing that is carried out at different times of day. In particular, it was hypothesized that subjects tested
in the morning tend to retain more of the exact wording of the text, whereas those tested in the afternoon are more likely
to produce a meaning-based representation. The results of a recognition test showed that, in agreement with other studies,
immediate text memory is better in the morning than in the afternoon. As predicted, the subjects tested in the morning better
remembered the exact wording of the original passages. However, the idea that memory for meaning is better in the afternoon
than the morning was not supported by the data. The results suggest that subjects at both times of day produce a meaning-based
representation of the text but, in the morning, this representation is supported by good verbatim memory, enabling accurate
recall of the text at that time. 相似文献
23.
This research examined the creative writing of 180 elementary school children for evidence of sex difference and sex-role perceptions. Stories were analyzed for frequency of male and female characters, attributes, and roles. Writers were equally divided by sex and into three age groups—grades 1–2, 3–4, and 5–6. Results suggest that the total number of characters, roles, and attributes was equivalent. However, the distribution of male and female characters, roles, and attributes differed with male and female writers. Female writers included significantly more female characters and assigned more attributes and roles to these characters. Nevertheless, in the stories of both male and female writers, there was a predominance of male characters and assignment of attributes and roles to male characters. The findings support the development and implementation of a nonsexist curriculum. 相似文献
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Jane A. Goldman Robert H. Lerman John H. Contois John N. Udall Jr. 《Journal of abnormal child psychology》1986,14(4):565-577
Despite speculation that sucrose consumption affects behavior, little empirical information is available. Accordingly, this study investigated the effect of sucrose consumption on the behavior of eight preschool children. Children were tested individually using a double-blind, crossover design. On separate mornings each child received 6 ounces of juice, sweetened on one morning with sucrose and on the other with an artificial sweetener. Children were observed for 90 minutes following the drinks, alternating between 15-minute sessions of work on structured tasks and 15-minute sessions of free play. Following the sucrose drink the children showed a decrement in performance in the structured testing situation, and they demonstrated more inappropriate behavior during free play. These differences in behavior were most pronounced approximately 45 to 60 minutes after the drinks. Thus, the study provides objective evidence in young children of a rather subtle, yet significant, time-dependent behavior effect of sucrose ingestion.This research was funded in part by grants from the General Research Grants Committee, University Hospital, Boston University Medical Center, and from the University of Connecticut Research Foundation. The project was conducted at the Clinical Research Center, Massachusetts Institute of Technology (National Institute of Health/General Clinical Research Center Grant 5M01-RR00088-20). We would like to express our appreciation to the many staff members of the Clinical Research Center for their extensive cooperation in helping us to plan and carry out this study, and to the director and staff of Technology Children's Center for their assistance in helping us to reach interested families. We also would like to thank the parents and children who participated in the study. Portions of this paper were presented at the annual meeting of the American Psychological Association, Toronto, August 1984. 相似文献
28.
Modest decrements in both taste threshold sensitivity and, more recently, suprathreshold sensitivity have been associated with the aging process. The present study was designed to investigate the existence of changes in preference for various concentrations of single tastes and of the same single tastes in more complex chemosensory mixtures. In this study, 300 participants from three different age groups (18-26, 32-45, over 65) rated for pleasantness four concentrations of sodium chloride, sucrose, and citric acid presented in both aqueous and beverage bases. Results showed significant effects of age, stimulus background, stimulus, concentration, and of several interactions, and they suggest that elderly subjects find salt and sugar pleasanter at higher concentrations than younger subjects do. 相似文献
29.
Lawrence R. Murphy David DuBois Joseph J. Hurrell 《Journal of business and psychology》1986,1(1):5-18
The deleterious effects of occupational stress on worker health and well-being have been described in numerous reports for a wide range of work groups. Work overload (and underload), deadline pressures, role Stressors, underutilization of abilities, and physical discomfort have been identified as work factors associated with increased stress symptom reporting. The relationship between work stress and accident/injury occurrences is less clearly documented, although scattered reports in the literature suggest a contributory role for stress in the accident process. In this article, data linking stress to unsafe work behavior are reviewed and a model is proposed wherein accidents can arise from impaired worker capabilities (e.g., slower reaction time) brought about by stress symptom activity (e.g., anxiety). The potential usefulness of stress management training (SMT) for shortcircuiting the stress/accidents cycle by alleviating stress symptoms is discussed in light of recent empirical research.Portions of this article were presented at the Third Annual Scientist/Practitioner Conference in Industrial/Organizational Psychology, Virginia Beach, Virginia, October, 1982. 相似文献
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