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41.
A tether system has been developed for continuous monitoring of blood pressure in the micropig. The micropig is a suitable model for blood-pressure research because of the similarity of its cardiovascular system to that of humans and because of its sensitivity to high sodium intake. The system consists of a metal boom, attached via a universal joint to a wall 6 ft above floor level, that extends horizontally to the center of the enclosure. A fluid and electronic swivel affixed to the boom is connected to a flexible, hollow, metal tether that descends to a vest worn by the micropig. The vest contains a pressure transducer to which an indwelling arterial catheter is connected via a stopcock. The transducer cable and an infusion line ascend through the interior of the tether to the swivel. The system remains in equilibrium through a system of pulleys and counterweights. Continuous, 24-h recording shows a diurnal variation characterized by higher heart rate but lower blood pressure during the day than at night. The system has been found to be effective for continuous studies over intervals of a month or more. 相似文献
42.
Jonathan Grainger J. Kevin O’Regan Arthur M. Jacobs Juan Segui 《Attention, perception & psychophysics》1992,51(1):49-56
Two experiments are described that measured lexical decision latencies and errors to five-letter French words with a single higher frequency orthographic neighbor and control words with no higher frequency neighbors. The higher frequency neighbor differed from the stimulus word by either the second letter (e.g.,astre-autre) or the fourth letter (chope-chose). Neighborhood frequency effects were found to interact with this factor, and significant interference was observed only tochope-type words. The effects of neighborhood frequency were also found to interact with the position of initial fixation in the stimulus word (either the second letter or the fourth letter). Interference was greatly reduced when the initial fixation was on the critical disambiguating letter (i.e., the letterp inchope). Moreover, word recognition was improved when subjects initially fixated the second letter relative to when they initially fixated the fourth letter of a five-letter word, but this second-letter advantage practically disappeared when the stimulus differed from a more frequent word by its fourth letter. The results are interpreted in terms of the interaction between visual and lexical factors in visual word recognition. 相似文献
43.
William Harman 《Religion》1989,19(4)
Current scholarly understandings of ‘sacred marriage’ are seriously impaired by work that focuses on ancient cultures, primarily in the Near East, but also in Greece. Even when ‘diffusionism’, ‘patternism’, and an apparent preoccupation with rituals presumed sexual are all factored out, modern scholars offer little new because they appeal to rituals never witnessed and to fragmentary texts which we can only hope had some connection to ritual. Focusing on an extant ritual tradition in India with a 200-year-old festival and an explicitly associated text from the 13th century
, Harman suggests that here, at least, sacred marriage is an elaborate, ritual statement of kinship responsibilities and obligations reestablished each year among deities and between deities and selected human beings. 相似文献
44.
Insight without awareness: On the interaction of verbalization, instruction and practice in a simulated process control task 总被引:5,自引:0,他引:5
William B. Stanley Robert C. Mathews Ray R. Buss Susan Kotler-Cope 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》1989,41(3):553-577
Four experiments in which subjects learned to control two versions of a complex simulated process control task show that verbalizable knowledge of procedures used to perform these tasks is very limited and is acquired late in learning. Individual learning curves associated with these tasks showed sudden improvements in performance, which were not accompanied by a similar increase in verbalizable knowledge. It was also found that verbal instructions consisting of exemplar memorization, strategies for rule induction, simple heuristics, and experts' instructions were all effective in enhancing novice subjects' performance. A theoretical framework is proposed in which subjects draw on two separate but interacting knowledge structures to perform these tasks. One knowledge structure is based on memory for past experiences (close analogies), and the other is based on one's current mental model of the task. Implicit sets of competing rules that control response selection are derived from both sources of knowledge. It is suggested that dissociations between task performance and verbalizing occur because memory-based processing tends to have more control over response selection because of its greater specificity, whereas a mental model tends to be the preferred mode for verbal reporting because of its greater accessibility. 相似文献
45.
The Sentencing Reform Act of 1984, which created the U.S. Sentencing Commission, required that the commisson consider prison capacity in drafting sentencing guidelines. As part of the commission's efforts to meet this requirement, we developed a computer simulation capable of projecting the impact of the commission's guidelines on future sentences and prison populations. According to our projections, “straight” probation sentences will be reduced significantly under the guidelines. However, reducing the use of probation will generate only modest demands on the prisons, and then mostly for community corrections phased in over the course of 5 years. We also project that, while average time served for violent offenses will increase substantially, average time served for most property crimes will remain largely the same. Finally, while we forecast that federal prison populations will grow markedly by the end of this century, this is more a result of the Anti-Drug Abuse Act of 1986 and the career offender provision of the Comprehensive Crime Control Act of 1984 than a result of the guidelines. 相似文献
46.
William J. Ruth Raymond DiGiuseppe 《Journal of Rational-Emotive & Cognitive-Behavior Therapy》1989,7(4):237-252
A single case study (n=1) conducted during therapy investigated the relationship between disputing irrational beliefs in vivo and setting and response generalization. Irrational beliefs associated with the subject's anger and depression were disputed at different intervals over a ten week period utilizing a multiple baseline design across four classes in a school setting (setting 1). Depression and anger were rated several times each week. The subject's level of anxiety was also rated in setting 1 but the irrational beliefs associated with it were not disputed. Anger, depression, and anxiety were rated without disputation in a separate work setting (setting 2). Affect ratings significantly decreased across both settings throughout the ten week period. Results indicated that 1) disputing irrational beliefs associated with anger and depression in setting 1 led to reductions in anxiety in this setting (response generalization), 2) anger and depression reductions in setting 2 paralleled setting 1 reductions (setting generalization), and 3) anxiety reductionsWilliam J. Ruth, PhD, Staff Psychologist and practicum supervisor, Institute for Rational-Emotive Therapy, NY City; School Psychologist, Board of Cooperative Educational Services, Southern Westchester.Raymond DiGiuseppe, PhD, ABPP, Director of Training and Research, Institute for Rational-Emotive Therapy, NY City; Graduate Professor, St. John's University, NY City; co-author,Practitioner's Guide to Rational-Emotive Therapy and RET with Alcoholics and Substance Abusers. 相似文献
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49.
The purpose of the present paper is to describe and compare some inexpensive software packages that calculate a variety of statistics on microcomputers running MS-DOS. For each package, hardware requirements, program capabilities, limitations, accuracy, error handling, and other features are considered. 相似文献
50.
David A. Washburn William D. Hopkins Duane M. Rumbaugh 《Behavior research methods》1989,21(2):281-284
Researchers interested in studying discrimination learning in primates have typically utilized variations in the Wisconsin General Test Apparatus (WGTA). In the present experiment, a new testing apparatus for the study of primate learning is proposed. In the video-task paradigm, rhesus monkeys (Macaca mulatta) respond to computer-generated stimuli by manipulating a joystick. Using this apparatus, discrimination learning-set data for 2 monkeys were obtained. Performance on Trial 2 exceeded 80% within 200 discrimination learning problems. These data illustrate the utility of the video-task paradigm in comparative research. Additionally, the efficient learning and rich data that were characteristic of this study suggest several advantages of the present testing paradigm over traditional WGTA testing. 相似文献