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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   
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Age-related differences in the pleasantness of chemosensory stimuli   总被引:2,自引:0,他引:2  
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   
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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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The purpose of the present experiment was to investigate the efficacy of a goal orientation procedure in their treatment of apathy, isolation, and insufficient goal setting skills in chronic psychiatric residents. The experiment was conducted in a behaviorally-oriented deinstitutionalization program in a state psychiatric hospital. Three male and four female chronic psychiatric residents served as research participants. A group repeated measures design with four within-participant phases (ABA‘B’) was utilized. The goal orientation procedure included a written schedule that was completed by each research participant daily. This Daily Living Schedule required that a behavior be specified by the participant for every half-hour period during the day (8:30 a.m. to 9:00 p.m.). During all four phases of the experiment, research participants were observed on the ward from 8:30 a.m. to 12:00 noon and 1:00 p.m. to 5:00 p.m. for engagement in scheduled target behaviors. The daily scheduling procedure produced substantial increases in appropriate behavior such as social activities, ward jobs, and participation in treatment programs, whereas decrease were produced in inappropriate behavior such as isolation and day time sleeping.  相似文献   
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We test the hypothesis that COVID-19 vaccine hesitancy is attributable to distrustful complacency—an interactive combination of low concern and low trust. Across two studies, 9,695 respondents from different parts of Britain reported their level of concern about COVID-19, trust in the UK government, and intention to accept or refuse the vaccine. Multilevel regression analysis, controlling for geographic area and relevant demographics, confirmed the predicted interactive effect of concern and trust. Across studies, respondents with both low trust and low concern were 10%–22% more vaccine hesitant than respondents with either high trust or high concern, and 26%–29% more hesitant than respondents with both high trust and high concern. Results hold equally among White, Black, and Muslim respondents, consistent with the view that regardless of mean-level differences, a common process underlies vaccine hesitancy, underlining the importance of tackling distrustful complacency both generally and specifically among unvaccinated individuals and populations.  相似文献   
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Animal Cognition - Experiments are widely used to investigate the behaviour and cognition of animals. While the automation of experiments to avoid potential experimenter bias is sometimes possible,...  相似文献   
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