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141.
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A survey in an unincorporated urban area compared the major community problems of concern to two groups: (a) a randomly selected sample of listed telephone subscribers, and (b) community leaders identified through nominations and reputational methods. In addition to asking about the major problems of the community, the randomly selected telephone subscribers were also asked to indicate for each problem (a) the persons or organizations to whom they looked for information and advice, (b) whom they considered qualified to speak for them, and (c) whom they expected to act in their behalf in the solution of these problems. The results of these surveys showed a large divergence of concerns expressed by the random samples and the reputed community leaders, as well as a striking number of respondents who felt themselves to be without spokesmen.  相似文献   
143.
An apparatus suitable for conducting simultaneous or delayed matching-to-sample experiments with as many as eight comparison stimuli is described. Data are presented which indicate that pigeons are capable of performing such a task. It is concluded that the simultaneous matching-to-sample procedure with more than two comparison stimuli is an efficient means of obtaining information about discrimination capacity and that this procedure may be suitable for studying visual perception in infrahuman Ss.  相似文献   
144.
Exteroceptive control of response under delayed reinforcement   总被引:3,自引:3,他引:0       下载免费PDF全文
Three white rats, after 50 continuous reinforcements, were exposed successively, under dim illumination, to reinforcement delays of 1, 3, 5, 7.5, 10, 15, and 20 sec, with prolonged training at the 20-sec level. Behavior was maintained at each level, and an increase in interval was accompanied by an increase in post-reinforcement pause. Subsequently, under both 20- and 30-sec delays, the animals were tested during half of each daily session to determine the effect of introducing darkness during each delay interval. The result of this stimulus “support” was to regularize and increase response rate for each animal at both interval values.  相似文献   
145.
Background: In the DSM-5, the diagnosis of hypochondriasis was replaced by two new diagnositic entities: somatic symptom disorder (SSD) and illness anxiety disorder (IAD). Both diagnoses share high health anxiety as a common criterion, but additonal somatic symptoms are only required for SSD but not IAD. Design: Our aim was to provide empirical evidence for the validity of these new diagnoses using data from a case–control study of highly health-anxious (n = 96), depressed (n = 52), and healthy (n = 52) individuals. Results: The individuals originally diagnosed as DSM-IV hypochondriasis predominantly met criteria for SSD (74%) and rarely for IAD (26%). Individuals with SSD were more impaired, had more often comorbid panic and generalized anxiety disorders, and had more medical consultations as those with IAD. Yet, no significant differences were found between SSD and IAD with regard to levels of health anxiety, other hypochondriacial characteristics, illness behavior, somatic symptom attributions, and physical concerns, whereas both groups differed significantly from clinical and healthy controls in all of these variables. Conclusion: These results do not support the proposed splitting of health anxiety/hypochondriasis into two diagnoses. Further validation studies with larger samples and additional control groups are warranted to prove the validity of the new diagnoses.  相似文献   
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