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881.
The need for common pedagogical and design features in courseware is discussed. A particularly useful feature would allow use of courseware in either of two “modes”: as an “electronic chalkboard” for the instructor who wishes to take advantage of the computer in a traditional lecture setting, or as an “electronic study guide” in which students interact individually with the programs. Development of programs using these two modes can be facilitated using Author-Assist, a set of routines and a program skeleton being developed by CONDUIT (1983). Author-Assist provides procedures for use of several types of automatic menu generation, automatic text formatting in “text ports,” mixed text and graphics, protected input routines, lowercase characters in text, automatic scaling of graphic displays using “graphports,” on-screen calculator functions, and a variety of other features.  相似文献   
882.
A survey of academic psychologists was taken to determine present use of computers in instruction, willingness to use good education software, and kinds of potential uses of computers in psychology courses. A majority of the respondents reported using computers in instruction. Respondents indicated substantial willingness to adopt computer-based courseware. Respondents believed that a variety of uses, including classroom demonstrations and student experiments, would facilitate student learning. The results of the survey are compared with the instructional modules the task force is developing.  相似文献   
883.
The concepts of informed consent and surveillance of human research designed to protect human subjects is commendable. The regulations of the Institutional Review Board (IRB) are having a major impact on clinical cancer research. There is greater administrative time needed of the investigator, the mechanisms of patient care have become cumbersome and some patients reject optional medical management that could be life saving. IRB regulations must be flexible to meet the needs of human subjects as well as those of the clinical investigator.  相似文献   
884.
Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations is addressed. Sampling differences for small species occupying relatively small home ranges indicate that fewer locations may be sufficient to allow for a reliable estimate of home range. Intraspecific variability in social status (group member, loner, resident, transient), age, sex, reproductive condition, and food resources also have to be considered, as do season, habitat, and differences in sampling and analytical methods. Comparative data still are needed.  相似文献   
885.
886.
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males.  相似文献   
887.
Experiments 1 and 2 established children’s (mean age 3 years, 7 months) subject-relative and object-relative motion thresholds at 1°31.37′/sec and 1°9.33′/sec, respectively, speeds well above those found for adults. Experiment 3 established that preschoolers, like adults, attribute object-relative motion to the smaller of two objects, with the inducing properties of the larger stimulus greatest when it is surrounding rather than adjacent to a smaller stimulus. The inducing advantage of surroundedness was equivalent for a single-element square frame and a multielement six-dot frame.  相似文献   
888.
An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated.  相似文献   
889.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
890.
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