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171.
Few studies have examined the impact of children with genetic disorders and their unaffected siblings on family functioning. In this study, the reciprocal causal links between problem behaviors and maternal distress were investigated in 150 families containing a child with fragile X syndrome (FXS) and an unaffected sibling. Both children's behavior problems appeared to have strong, direct effects on maternal distress, but maternal distress did not appear to have any reciprocal causal effects on either child's behavior problems. Surprisingly, there were no significant differences in the effects of the two children's behavior problems on maternal distress. These data suggest that the problem behaviors of children with FXS, as well as their unaffected siblings, can have a substantial and additive impact on maternal depression and anxiety. Future research efforts should employ longitudinal research designs to confirm these findings.  相似文献   
172.
This paper is a case report of an Hawaiian near-death experience (NDE) from the early 1900s, which was uncovered in a turn-of-the-century monograph of Hawaiian folk tales (Thrum, 1907). The account differs from others in the same volume because it appears to be a real-life account rather than a folk tale. I describe similarities and differences from other Pacific area accounts, with particular attention to the only other Polynesian NDE account in the literature, a Maori NDE reported by Michael King in 1985.  相似文献   
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The paper presents a core theory of human plausible reasoning based on analysis of people's answers to everyday questions about the world. The theory consists of three parts:
  • 1 a formal representation of plausible inference patterns; such as deductions, inductions, and analogies, that are frequently employed in answering everyday questions;
  • 2 a set of parameters, such as conditional likelihood, typicality, and similarity, that affect the certainty of people's answers to such questions; and
  • 3 a system relating the different plausible inference patterns and the different certainty parameters.
This is one of the first attempts to construct a formal theory that addresses both the semantic and parametric aspects of the kind of everyday reasoning that pervades. all of human discourse.  相似文献   
177.
This article presents a framework for assessing the institutionalization of programmatic innovations in nonprofit community agencies and in schools. Institutionalization is the attainment of long-term viability and integration of innovations in organizations. Institutionalization is often characterized as the final stage in an innovation diffusion process. The framework was derived from a qualitative study of ten health promotion programs that were innovations in their host organizations. The framework is a two dimensional matrix: one dimension consists of organizational subsystems; the other consists of levels of institutionalization termed passages, routines, and niche saturation. The cells of the matrix are the basis for assessing program institutionalization. Robert M. Goodman is a research assistant professor in the Department of Health Behavior and Health Education at the University of North Carolina's School of Public Health. Currently, Dr. Goodman directs a four-year intervention study on the dissemination of tobacco prevention curricular funded by the National Cancer Institute. Allan Steckler is an associate professor in the Department of Health Behavior and Health Education at the University of North Carolina's School of Public Health. Dr. Steckler is also the principal investigator of the National Cancer Institute tobacco prevention study.  相似文献   
178.
Mathematics is often said to be a different language in itself. Three experiments were conducted to show some evidence for this common notion. It was hypothesized that in math word problem solving, people interpret words like “more” and “less” in specialized ways that are specific to the task of math word problem solving. Subjects were given texts with quantitative information, but the texts were framed either as math problems or as stories, and were written either in English or Filipino. Subjects were then asked to verify statements that describe quantitative relations given in the text; these relations either stated an exact or an inexact quantitative difference. The verification responses and verification times in three experiments show that subjects more often accepted the inexact difference as true when the text was framed as a story compared to when framed as a problem. These results support the hypothesis that the use of the specialized meaning is specific to the task of solving word problems in math. The data were equivocal about the role of the language used in the operation of this knowledge. The results were discussed in terms of the implications of specificity of knowledge, context sensitivity, and the possible role of language use in the process of learning and developing mathematical knowledge.  相似文献   
179.
Soft commitment: self-control achieved by response persistence.   总被引:4,自引:3,他引:1       下载免费PDF全文
With reinforcement contingent on a single peck on either of two available keys (concurrent continuous reinforcement schedules) 4 pigeons, at 80% of free-feeding weights, preferred a smaller-sooner reinforcer (2.5 s of mixed grain preceded by a 0.5-s delay) to a larger-later reinforcer (4.5 s of mixed grain preceded by a 3.5-s delay). However, when the smaller-sooner and larger-later reinforcers were contingent on a concurrent fixed-ratio 31 schedule (the first 30 pecks distributed in any way on the two keys), all pigeons obtained the larger-later reinforcer much more often than they did when only a single peck was required. This "self-control" was achieved by beginning to peck the key leading to the larger-later reinforcer and persisting on that key until reinforcement occurred. We call this persistence "soft commitment" to distinguish it from strict commitment, in which self-control is achieved by preventing changeovers. Soft commitment also effectively achieved self-control when a brief (1-s) signal was inserted between the 30th and 31st response of the ratio and with concurrent fixed-interval 30-s schedules (rather than ratio schedules) of reinforcement. In a second experiment with the same subjects, the fixed ratio was interrupted by darkening both keys and lighting a third (center) key on which pecking was required for various fractions of the fixed-ratio count. The interruption significantly reduced self-control. When interruption was complete (30 responses on the center key followed by a single choice response), pigeons chose the smaller-sooner reinforcer as frequently as they did when only a single choice response was required.  相似文献   
180.
Latent inhibition is a slowing of learning about a stimulus that when previously experienced had no consequences. This study investigated the effects of tobacco smoking and personality traits on a latent inhibition task. Two-hundred and five healthy adults performed an auditory masking task during which half of them were pre-exposed to bursts of white noise. All subjects were then asked to detect an association of the white noise with a change on a computer screen. Subjects who had heard the white noises before were slower to learn the association than subjects who had not, i.e. they showed latent inhibition. Latent inhibition was stronger when subjects were pre-exposed to 10 rather than 6 bursts of white noise. Latent inhibition was reduced in subjects who smoked tobacco and in non-smoking subjects who scored highly on a schizotypy questionnaire. These two effects were independent. We conclude that tobacco smoking should be taken into account in interpreting the results of human latent inhibition studies.  相似文献   
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