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161.
Let S be a deductive system such that S-derivability (s) is arithmetic and sound with respect to structures of class K. From simple conditions on K and s, it follows constructively that the K-completeness of s implies MP(S), a form of Markov's Principle. If s is undecidable then MP(S) is independent of first-order Heyting arithmetic. Also, if s is undecidable and the S proof relation is decidable, then MP(S) is independent of second-order Heyting arithmetic, HAS. Lastly, when s is many-one complete, MP(S) implies the usual Markov's Principle MP.An immediate corollary is that the Tarski, Beth and Kripke weak completeness theorems for the negative fragment of intuitionistic predicate logic are unobtainable in HAS. Second, each of these: weak completeness for classical predicate logic, weak completeness for the negative fragment of intuitionistic predicate logic and strong completeness for sentential logic implics MP. Beth and Kripke completeness for intuitionistic predicate or sentential logic also entail MP.These results give extensions of the theorem of Gödel and Kreisel (in [4]) that completeness for pure intuitionistic predicate logic requires MP. The assumptions of Gödel and Kreisel's original proof included the Axiom of Dependent Choice and Herbrand's Theorem, no use of which is explicit in the present article.  相似文献   
162.
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training.  相似文献   
163.
Two experiments explored whether the magnitude of the enactment effect in action memory (i. e., higher recall with motor than with non-motor encoding) may depend upon the use of individual or group testing procedures. Nonmotor encoding instructions, requiring the subjects to listen to orally presented action items, were compared to instructions which also required enactment. With encoding treated as a within-subject factor, the observations failed to reveal any significant difference between individual and group testing. With encoding treated as a between-subject factor, the results showed an interaction between test and encoding conditions, such that an enactment effect was found only with group testing. Different support value for auditory cues in group and individual test situations was assumed to account for this difference. In a third experiment the indicative and imperative verb forms were compared. An interaction was observed, showing that in Norwegian, enacted verbs were remembered better when presented in the indicative than in the imperative. No corresponding difference was found under non-enactment conditions. For this finding, a social interaction interpretation was offered.  相似文献   
164.
This study examined the effect of parental distress on mothers' and fathers' reports of children's emotional and behavioral problems. The subjects were the parents of 696 children aged 10 to 11 or 14 to 15 years living in two-parent families in the community. The study utilized an extended version of the model previously employed by Fergusson, Lynskey, and Horwood (1993) to examine the impact of maternal depression on mothers' reports of children's behavior. In the present study, the extended model was used to assess the impact of distress on reports of childhood externalizing and internalizing problems obtained from both mothers and fathers. The results suggested that distress had little influence on mothers' or fathers' reports of childhood behavior problems. It is concluded that in community studies the size of any bias in mothers' and fathers' reports of childhood behavior problems due to parental distress is likely to be very small and of little clinical significance.  相似文献   
165.
In this paper, it is proposed that a) psychosocial medicine is best taught in a setting that provides technical and emotional support, while seizing for teaching only those moments when the learner is most receptive; and b) that the setting should avoid the development of a separate psychosocial skills curriculum, but should take the student where he or she is and integrate the psychosocial skills into his or her everyday biomedical practice. The paper gives specific case examples in which family based psychosocial issues were preeminent in the clinical problem-solving medical residents faced.  相似文献   
166.
Multiple baseline designs were used to examine the effects of an instructional package on accuracy of performance in solving multiplication facts by 3 students with learning disabilities. The instructional package included the following components: (a) a modified instructional sequence in which multiplication facts were grouped into the zeros, ones, doubles, fives, and nines categories, and those remaining; (b) identification of the category in which each fact belonged; (c) mnemonic strategies associated with solving facts in each category; and (d) steps to be completed for solving facts in each category. Results indicated that the instructional package produced substantial and immediate effects. After receiving instruction, a participant's accuracy was often 100%, and this was maintained throughout the evaluation even as other strategies were introduced. Comparable results occurred across students, demonstrating replication of the effects of the instructional package.  相似文献   
167.
语句重音分布模式知觉   总被引:1,自引:1,他引:0  
杨玉芳 《心理学报》1996,29(3):225-231
在排除语义和句法结构信息的情况下,用统计方法研究听者使用局部的韵律学线索知觉语句重音分布模式的能力;并根据知觉模式,讨论汉语中重音分类、词重音在语流中的变化以及重音在语句组织和语义表达中的作用等问题。  相似文献   
168.
Parallel lives: Community psychology in Latin America and the United States   总被引:3,自引:0,他引:3  
Comparing the history of community psychology as it developed in the U.S. during the 1960s with the community psychology that developed 10 years later in Latin America, one is reminded of the title of Plutarch’s masterpice,Parallel Lives. Although there was very little contact or communication between the first community psychologists in these regions, very similar principles and orientations evolved. These similarities are particularly striking given the many ways in which the U.S. and Latin American contexts and histories differ. Since most readers are expected to be familiar with the history of community psychology as it developed in the U.S., this paper focuses primarily on the development of community psychology in Latin America in order to highlight areas of convergence as well as divergence from the U.S. experience. This paper is based on an address presented at the Fourth Biennial Conference, Society for Community Research and Action, Division 27 of the American Psychological Association, William and Mary College, Williamsburg, Virginia, 1993. The author acknowledges the valuable help received from J. R. Newbrough and from the referees in the revision of this paper.  相似文献   
169.
The 30-item Trainee Adjustment to Program Stress (TAPS) scale was developed to measure lifestyle stress of family therapy trainees. Initially, 70 items were generated from propositional statements based on four constructs. Following pilot testing, 329 out of 900 (37%) student members of the American Association for Mariage and Family Therapy (AAMFT) returned TAPS questionnaires. Internal consistency reliability analyses and principal components and factor analyses produced a final 30 item TAPS scale appropriate for use in family therapy training programs. Reliability and validity measures are reported.  相似文献   
170.
Practitioners in Hong Kong have shown an increasing interest in various family therapy approaches since the 1980s. This paper offers a critique of the major concepts and techniques of the Satir model applied to families in Hong Kong. Cultural considerations are examined in relation to the family structure and hierarchy, the Chinese self and self-esteem, communication patterns, and family rules. Implications for the application of the Satir model of family therapy in Hong Kong are discussed.  相似文献   
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