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941.
Acetaminophen (N-Acetyl-p-aminophenol) was administered intraperitoneally to 15 Sprague-Dawley rats partitioned into 3 studies (5 rats per study) using a within subjects, repeated-measures reversal design. Behavioral thermoregulation was assessed in a cold Skinner Box using 5-sec. exposures of microwave radiation [Specific Absorption Rate = 0.34 Watts/kg/(mW/cm2)] as reinforcing stimuli under a fixed-interval 2-min. schedule of positive reinforcement. Doses of 10, 20, 30, 40, and 50 mg/kg (in solutions of 1%, 2%, 3%, 4%, and 5%) acetaminophen showed stable rates of operant responding for heat compared with significant changes in rates for comparable doses of aspirin in a 1993 study by Vitulli, et al. Weight reductions and temperature increases varied significantly with before-session and after-session measures, respectively. 1994-95 biochemical data of Murphy, et al. from humans following aspirin or acetaminophen ingestion which affect thermoregulation and sleep patterns are discussed in conjunction with behavioral data from rats.  相似文献   
942.
943.
This article relates a theory of the duplex self constituted by consciousness and experienced as I and me to the various post-Freudian interpretations of the self.  相似文献   
944.
The present studies examined the nature of kinematic interlimb interference during bilateral elbow movements of 1:1, 2:1 and 3:1 frequency ratios and the manner in which subjects cope with coordination bias. Analysis of movement trajectories in the first experiment indicated progressively greater angular velocity assimilation across 2:1 and 3:1 conditions. The desired temporal relationship was maintained by slowing or pausing the low-frequency movement at peak extension while the high-frequency arm produced intervening cycles. An increase in amplitude was also evident for concurrent, homologous cycles. Movement smoothness was emphasized and additional practice was provided in a second experiment. This resulted in dissociated peak angular velocity between limbs and eliminated hesitations and amplitude effects. Bias was still evident, however, as an intermittent approach toward a 1:1 ratio within each cycle. This systematic tendency was somewhat greater at the lower of two absolute frequency combinations but was not influenced by the role of each arm in producing the higher or lower frequency movement. The findings from the first experiment suggest that subjects initially accommodate interlimb kinematic assimilation, while producing the intended timing ratio, by intermittently slowing or pausing the lower-frequency movement. This attenuates the need for bilaterally-disparate movement parameters and provides additional time for organizing residual kinematic differences, perhaps reducing transient coupling. Evidence from the second experiment indicates that subtle relative motion preferences are still evident following sufficient practice to perform the movements smoothly. The within-cycle locations of the points of greatest interlimb bias for the 2:1 rhythms were positively displaced from those previously observed for 1:1 oscillations. The persistent coordination tendencies noted in both experiments perhaps reflect an assimilation/compensation cycle and constitute one potential source of the systematic error that often emerges during the acquisition of complex skills.  相似文献   
945.
The purpose of this study was to examine the effect of learning to produce voluntarily a basic biomechanical mechanism, the stretch-shorten cycle (SSC), on the acceleration of a ballistic arm movement. The task required an elbow flexion at maximal effort performed with the forearm resting upon a horizontal manipulandum. Subjects in three groups received either no augmented feedback, feedback concerning the velocity of the flexion, or a combination of feedback on velocity and feedback related to the rate of stretch of the SSC during 80 training trials. The training trials were preceded by a pretest and followed by a posttest without feedback. Analyses showed that the subjects receiving feedback concerning the SSC exhibited earlier and greater peak angular acceleration than the other groups. These findings provide evidence that acquiring the control of relevant, basic mechanisms like the SSC may be useful in facilitating tasks requiring limb movements of maximal effort.  相似文献   
946.
947.
We used a multiple baseline design across teachers (with a reversal phase for 1 teacher) to evaluate the direct and indirect effects of a structured coaching procedure on the teaching behaviors of 3 day-care teachers. Structured coaching preceding daily caregiver routines resulted in (a) substantial increases in adult delivery of behavioral support of social interaction during group activities with 2- and 4-year-old children and (b) marked collateral increases in positive interactions of socially withdrawn children. Long-term maintenance effects were demonstrated by both the teachers and target children, and social validity measures indicated that the teachers rated coaching very positively on several dimensions. The results are discussed in relation to in-service training of day-care staff, the concept of coaching as a setting event, and the dissemination of teaching technology related to social interaction of young children.  相似文献   
948.
Twenty-five managers participated in two parallel 6-hour quasi-experimental simulations. On placebo treatment days, the subjects received hourly placebo drinks. On alcohol treatment days (order counterbalanced), enough alcohol was provided prior to the fourth hour of simulation participation to attain a breath alcohol level (BAL) of near 0.10. All other drinks contained a placebo beverage. Complex task performance was assessed on five variables derived from complexity theory, comparing performance for three measurement periods: (a) prior to the fourth hour of simulation participation (placebo treatment), (b) during the fourth hour (rising BALs on alcohol treatment days), and (c) during the fifth/sixth hours (falling BALs). Alcohol diminished the participants’ breadth of approach (differentiation). Performance on indicators of strategic functioning (integration) decreased after BALs had begun to fall but not while BALs were rising. The implications for performance of complex tasks under the influence of alcohol and for the applicability of the acute tolerance phenomenon to complex task environments are considered.  相似文献   
949.
The present paper focuses on the extraction, by means of aformal logical/mathematical methodology (i.e., automatically, exclusively by rule), of concept content, as in, for example, continuous discourse. The approach to a fully formal definition of concept content ultimately is owing to a German government initiative to establish “standards” regarding concepts, in conjunction with efforts to stipulate precisely (and then, derivatively, through computer programs) data and information needs according to work role in certain government offices.  相似文献   
950.
A number of common problems plague the teaching of the undergraduate research methods course, from the training of teaching assistants to providing meaningful experimental materials to handling data acquisition and analysis. The Student Micro Experimental Laboratory (MEL) offers a systematic approach to the management of a computerized research methods laboratory course by combining high-quality experiments in many areas of psychology with background materials to help the instructor and teaching assistant. The software presents and collects data from 28 experiments. The data can be analyzed for single subjects and for classes as a whole. Students can rapidly implement new experiments in a variety of paradigms. An expanding library of experiments created by students and instructors should provide an expanding environment for teaching experimental research methods. Instructor’s materials provide background information, discussion questions, and data analysis for all experiments. The student workbook provides discussion of the background of the experiment, details of the methodology, and questions addressing various aspects of experimental design and interpretation of data.  相似文献   
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