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111.
The development of a phenotype is due to an interaction of the genotype with the environment. Two terms have been used to describe the outcome of this interaction, the norm-of-reaction and the reaction range. The first represents the theoretically limitless distribution of the phenotypes that may be expressed by a given genotype. The reaction range implies an upper and lower limit for phenotype expression possible from a given genotype. A critical distinction between the reaction range and the norm-of-reaction is that the norm-of-reaction is a statement of the conceivable interactions found but does not imply any predictability other than that within the conditions previously tested experimentally, that is, the tails of a normal distribution are infinitely variable, whereas the concept of reaction range implies a limitation inherent in the genotype, that is, a finite range. Empirical support for the reaction-range concept is questionable. Animal studies cited in support of the reaction range have been inappropriately and incorrectly interpreted.  相似文献   
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113.
The authors discuss the application of Gestalt theory as a means of dealing with the surviving classmates of a student who committed suicide.  相似文献   
114.
We outline a BASIC program and subsidiary machine language timing routines that enable the Apple II series of computers to be employed as control devices for the tachistoscopic presentation of 35-mm slides and the collection of response latencies. The program is functional for experiments that require pictorial stimuli to be presented in up to three separate fields, with precise display times, precise interstimulus and intertriai intervals, and the collection of manual or vocal reaction times with millisecond accuracy. The major advantages of this system are that initial setup costs are substantially lower than those for other similar systems (e.g., Loftus, Gillispie. Tigre, & Nelson, 1984) and that user customization of the program may be accomplished by anyone possessing rudimentary knowledge of the BASIC programming language.  相似文献   
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116.
Thirty children and 5 adults participated in two experiments designed to compare visual processing in normal and reading disabled children. The children were aged 8, 10, and 12 years. In Experiment 1, subjects were asked to detect the temporal order of two briefly presented stimuli. In Experiment 2, subjects sorted cards containing bracket stimuli that did or did not produce perceptual grouping effects. Poor readers required more time to make accurate temporal order judgments and showed stronger perceptual grouping effects. For both good and poor readers, the amount of time necessary to make a correct temporal order judgment decreased, and perceptual grouping effects became weaker with age. However, the magnitude of the difference between the groups did not lessen with age. These results suggest that there are visual processing differences between good and poor readers that do not appear to correct by age 12.  相似文献   
117.
Differences in school behavior and achievement between students from intact, reconstituted, and single-parent families were analyzed. Students from intact two-parent families had fewer absences and tardies, higher grade point averages, and fewer negative and more positive teacher behavioral ratings than did those from reconstituted and single-parent families.  相似文献   
118.
Using the metaphor of ecumenism, the current status of psychoanalysis and the American Psychoanalytic Association is examined. The dialectical tendencies to oppose and to unify are noted in psychoanalytic theory, technique, and practice, as well as in the administrative and political life of our organization. Fostering tolerance for new hypotheses without sacrificing empirical discrimination, and promoting broad participation without lowering standards confront us as major tasks demanding continuing vigilance and effort.  相似文献   
119.
Seventh-grade students and teachers from twenty-three middle and junior high schools were surveyed to determine the association between teacher attitudes, behavioral intentions, and smoking behavior and the prevalence of student smoking. Teacher attitudes toward smoking policies were found to be strongly related to the current smoking behavior of the teacher but not consistently related to student smoking. In addition, teacher likelihood of intervening showed a modest association with teacher smoking status, with current smokers generally indicating being the least likely to intervene for student possession or use of cigarettes. Teacher intentions to intervene were strongly associated with the prevalence of smoking among boys but not girls.  相似文献   
120.
The present study attempted to delineate factors that are associated with and may contribute to juvenile delinquency. Delinquents were compared to a matched control group of nonoffenders on a measure of mental health problems. Twenty-four male and female incarcerated juvenile offenders and 24 nonoffending adolescents were evaluated on the Revised Behavior Problem Checklist (RBPC). As expected, the offenders scored higher (an indication of more psychopathology) on the subscales of the RBPC which represent externalizing types of problems. The offenders also scored significantly higher on the subscales reflecting internalizing problems and psychotic behavior. The results of this study point to the importance of assessing and treating offenders, especially those who are incarcerated, for difficulties other than externalizing problems.  相似文献   
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