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41.
This systematic review examines 35 empirical studies featuring the use of think-aloud interviews in computational thinking (CT) research. Findings show that think-aloud interviews (1) are typically conducted in Computer Science classrooms and with K-12 students; (2) are usually combined with other exploratory CT assessment tools; (3) have the potential to benefit learners with special needs and identify the competency gaps through involving diverse participants; (4) are conducted in the absence of cognitive models and standard procedures; and (5) display insufficient definitional and methodological rigor. Theoretically, this review presents a systematic assessment about the application of think-aloud interviews in CT studies and identifies the limitations in existing CT-related think-aloud studies. Practically, this review serves as a reference for studying the cognitive processes during CT problem-solving and provides suggestions for CT researchers who intend to incorporate think-aloud interviews in their studies.  相似文献   
42.
The plastic barrel suit provides complete protection of chronically implanted fistulas and electrical connectors. The lost time, expense, and the frustrations of having these devices damaged was avoided.  相似文献   
43.
Wayne Lee 《Psychometrika》1966,31(3):397-412
A method of design symbolization (DS) is given for a class of designs in which all factors are related by complete crossing or by nesting. Characterization of acceptable DS's, and logical relational properties are given. It is shown how the design model can be obtained from the DS.The preparation of this article was supported by NIH Grant GM-11128, and by grants to the Institute of Human Learning by NSF and NIH.  相似文献   
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The 3RT Test consists of a simple, a choice, and a conditional reaction time (RT) task. The three tasks involve comparable visual stimuli and require identical manual responses, but they differ in the complexity of cognitive processing required. The nonverbal stimuli convey commonly known meanings. Responses can be made either on the keyboard or on response keys connected to the computer’s serial port. The computer’s internal timer/counter is used for millisecond timing. The test administration program allows flexible setting of the test conditions. The data analysis program provides summary data not only for each RT task as a whole, but also for separate trial types within each task. Summary statistics include measures of variation and central value that are not affected by extreme scores. In addition to laboratory studies with normal adults, the 3RT Test is suitable for life-span developmental studies, cross-cultural comparisons, and other uses in various clinical settings.  相似文献   
46.
Tolbutamide has previously been shown to amplify the pressor effects of “exogenous” catecholamines in conscious dogs, possibly due to sensitization of the α1-adrenoreceptor-mediated vasoconstriction. The objective of this study was to examine if tolbutamide also amplifies the pressor effects of “endogenous” catecholamines released during psychological stress (classical Pavlovian aversive conditioning). Experiments were conducted in β-adrenoreceptor-blocked (propranolol, 1 mg/kg, i.v.) conscious dogs (n=4) trained in classical aversive conditioning. Conditioning was accomplished by following a tone (CS+) with a 1/2 second shock; another tone (CS-) was not followed by any shock and served as control. With saline pretreatment, aversive conditioning (i.e., CS+) increased mean arterial pressure (MAP) only by approximately 4.7% when compared to CS-, whereas with tolbutamide (45 mg/kg, i.v.) pretreatment, the increase in MAP induced by CS+ beyond what was induced by the CS- (approximately 6.2%) was significantly (p<0.05) larger than that with saline pretreatment. In isolated canine femoral arterial segments (n=4), the vasoconstrictor effect of phenylephrine (an α1-agonist) at 5×10?6M (which was the EC50 value) was amplified by 2×10?2M of tolbutamide from 54.0±2.0% to 66.9±2.1%. In conclusion, tolbutamide amplifies the pressor effects of “endogenous” catecholamines in conscious dogs, possibly by sensitization of the α1-adrenoreceptor-mediated vasoconstriction. This mechanism of action is novel and has not been reported with other agents.  相似文献   
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48.
Some hypotheses concerning the evolution of polysemous words   总被引:1,自引:0,他引:1  
The evolution of polysemous words is examined in three studies. Study 1 indicates that older words are more polysemous than recent words, and that frequently used words are more polysemous than infrequently used words. These effects were replicated, controlling for word concreteness (Study 2) and evaluation (Study 3), using two other samples of words. If words evolve additional meanings through metaphor (MacCormac, 1985), then variables (such as concreteness and evaluation) that play a role in metaphor may mediate the evolution of polysemy. The correlation between concreteness and polysemy was negligible (Study 2). As hypothesized, evaluation is a significant predictor of polysemy: Negative words are more polysemous than positive words, and relatively neutral words are more polysemous than evaluatively extreme words. These findings are consistent with the notion that polysemous words evolve, in part, through metaphor.  相似文献   
49.
自由回忆和线索回忆测验中的系列位置效应   总被引:3,自引:1,他引:2  
吴艳红  朱滢 《心理科学》1997,20(3):217-221
本文以96个中国汉字为材料,使用自由回忆和线索回忆测验方法,对20名被试进行6组分测验和最后所有汉字的总测验。发现自由回忆分测验中存在明显的系列位置效应,总测验出现负近因现象;线索回忆分测验也表现出明显的系列位置效应,但最后的总测验没有出现负近因现象。上述结果验证了Bjork和Whitten(1974)提出的顺序或情景理论。  相似文献   
50.
A total of 229 late adolescents (a large majority 15 to 19 years of age) completed a questionnaire that assesses a broad range of videogame-relevant experiences, preferences, and attitudes. Videogame playing was found to be a more popular, and a more highly regarded, activity among males than females. Gender differences were also found in participants' ratings of their motivations for playing videogames, their evaluations of particular characteristics of videogames, and their selection of their “most favorite” videogame. The differences between frequent and infrequent videogame players appeared to be limited to differences in the extent to which videogame playing is pursued and evaluated as a positive leisure activity, rather than reflecting broad differences in interest or personality. Some relations were found between participants' self-reported personality characteristics (i.e., self-esteem, empathy, conscientiousness, and introversion) and their attitudes toward videogames.  相似文献   
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