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951.
KCl water preference was examined in diet-replete, sodium-and sodium—potassium-deficient postpubertal rats of different ages. While diet-replete rats displayed a KCl preference-aversion profile similar to that found using other salts, when retested 30 days later, these same animals had no KCl preference. Na-and Na—K-deficient rats preferred KCl over a broad range of concentrations when tested in early postpuberty and the Na—K-deficient group had a markedly reduced KCl preference threshold (0.12%) when compared to all other groups in the study. But Na-and Na—K-deficient rats older by 2 1/2 months did not prefer KCl. The notion of specific food hungers can be invoked to account for some of the preferences. But hedonics, age and KCl experience must also be considered based on (1) the quantities of KCl consumed, (2) the preference reversals within animals, as well as (3) the significantly increased heart—and kidney—body weight ratios in the rats with the greatest KCl preference.  相似文献   
952.
The apparent heaviness of a set of 40 cylindrical objects was scaled by the method of magnitude estimation. The objects varied in weight, volume. and density. There were three main conclusions: (1) For any constant volume, heaviness grows as a power function of weight; the larger the volume. the larger the exponent of the power function. The family of such power functions converge at a common point in the vicinity of the heaviest weight that can be lifted. (2) For any constant density (i:e., weight proportional to volume), heaviness does not grow as a power function of weight. (3) For any constant weight, heaviness decreases approximately as a logarithmic function of volume; the constants of the log function depend systematically on the weight of the object. The outcome furnishes a broad quantitative picture of apparent heaviness and of the size-weight illusion (Charpentier’s illusion).  相似文献   
953.
A model for a score based on an interview is presented which identifies the effect due to the subject, to the manner in which the interviewer tends to conduct his interviews, to the criteria he tends to use in scoring subjects' responses, to the compromises he tends to adopt between the demands of interviewing and those of scoring, and to chance errors. A suggested experimental design calls for each ofK investigators to interview a different sample ofN subjects, but for all investigators to score each subject. The drawing of inferences when interest is only in theK participants in the reliability study is considered, and a numerical example is given.This work was supported in part by grant DE R01 00793 from the National Institute of Dental Research, and in part by grants MH 08534 and MH 09191 from the National Institute of Mental Health, and forms part of the author's Ph.D. dissertation at Columbia University. The guidance provided by Professor T. W. Anderson is gratefully acknowledged.  相似文献   
954.
955.
Cotherapy in a training relationship with a senior therapist/supervisor and a trainee/junior leader is presented. A structured training year with planned sessions for the junior leader to lead the group alone, as well as intensive supervision, is described. The training relationship is seen as evolving into an egalitarian, collegial working relationship. An incidental benefit of this cotherapy approach is that additional opportunities are provided for group members to work through attitudes, feelings, and behaviors associated with attachment, interpersonal relationship (autonomy and affiliation), separation, and loss. Potential drawbacks and applications are also noted.The authors express their appreciation to the many group members and cotherapists whose experiences provided the stimulation and clinical material for the present formulation.  相似文献   
956.
We consider the issue of what an agent or a processor needs to know in order to know that its messages are true. This may be viewed as a first step to a general theory of cooperative communication in distributed systems. An honest message is one that is known to be true when it is sent (or said). If every message that is sent is honest, then of course every message that is sent is true. Various weaker considerations than honesty are investigated with the property that provided every message sent satisfies the condition, then every message sent is true.This is an expanded version of a paper that appears in the Proceedings of the Second IEEE Symposium on Logic in Computer Science, 1987.  相似文献   
957.
Eighteen 15-week-old, normal full-term infants were presented with photographic slides of a human facial expression. The infant's heart rate, body movement, and visual attention were recorded simultaneously. The results showed that heart rate and body movement were significantly correlated during visual attention but not during inattention. Both heart rate and body movement decelerated significantly when the infants visually attended to the target stimulus. The results are discussed with reference to cardiac-somatic integration in early infancy and its implication as a possible index of attention.  相似文献   
958.
This study examines a series of coronary artery bypass patients (CABS) for neuropsychological and regional cerebral blood flow (RCBF) changes at 8 days and 8 weeks post surgery. Seventy-three percent were found to have moderate or severe neuropsychological deficits at 8 days post operation and 37% at 8 weeks post surgery. A comparison group of major vascular and thoracic surgery patients was also found to have a significant proportion of neuropsychological deficit following surgery. The RCBF assessments indicated a significant drop in mean RCBF at 8 days post surgery in the coronary artery bypass group which did not persist to 8 weeks. The comparison group showed no changes in RCBF following surgery. The findings suggest different patterns of recovery and origins of the neuropsychological deficit in the two groups and emphasize the need for appropriate control groups in studies examining the cortical effects of extracorporeal circulation. In addition, the project received generous support from the special trustees of the Middlesex Hospital.  相似文献   
959.
The effect of cue reliability was tested in a two-cue multiple-cue probability learning (MCPL) task. Subjects were 42 undergraduates. The cue validities were.78 and.37. Unreliability in a cue was defined as variability in multiple observations of that cue on a given trial. That variability was provided by adding random errors to the true value of the cue. One group was given consistent cues (i.e., the more valid cue was the more reliable cue), one group was given inconsistent cues, and the control group was given true scores. Cue reliability did not affect subjects' consistency or achievement, but did interact with the presence of outcome feedback. The subjective weights showed that subjects thought they weighted the more reliable cue more heavily regardless of the cue validities or their actual cue weightings. There were wide individual differences in performance, illustrating the need for an idiographic-statistical approach in studying decision making.  相似文献   
960.
We examined the effect of voice-feedback delay on learning to type nonsense strings on a reduced computer terminal keyboard. The results suggest that long delays (1,642 msec) affect learning of the keyboard before mastery, whereas shorter delays (841 msec) do not. With mastery, subjects learn to ignore the disruptive effects of long feedback delays. Feedback delay may nevertheless be an important human-factors issue for blind consumers who are learning to type with a voice-based system, and for hardware and software designers of systems for the blind and visually impaired.  相似文献   
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