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Recent studies have called for the abandonment of the relative-time-spent scale in task inventories. This recommendation is based on findings that the job profile created with the scale data is highly correlated with the profile created from a much simpler “Do you perform this task?” checklist. We examined this issue using 3 inventories and 42 jobs (N=2252). Profile correlations were computed on only the tasks actually performed by incumbents to avoid possibly inflated rs due to including irrelevant tasks. The specificity of task inventory items was proposed as an explanation for the high correlation between the two job profiles. Specificity of items was examined by looking at both the type (job duties versus tasks) and the amount (number of items in job profile and average number of items relevant to each job) of items used in the inventory. Correlations between time spent and checklist profiles were in the .80's and .90's regardless of the number of irrelevant tasks or the specificity of tasks. We agree with previous military research and conclude that the relative-time-spent scale has limited incremental utility beyond a dichotomous checklist.  相似文献   
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Although cerebral anoxia is not thought to be responsible for triggering near-death experiences (NDEs), the issue is not so clear in the case of hypercapnia. Detection of normal blood gases in Michael Sabom's (1982) case study seems to be the major reply to suggestions that hypercapnia may have a causal role in NDEs. We argue, however, that routine arterial measures of blood gases are not a reliable indicator of cerebral levels.  相似文献   
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The paper is an attempt to review the basis for the claim that physicians have a professional obligation to treat AIDS patients. Considered are the historical record, two professional codes of ethics, and several recent articles. The paper concludes that the arguments considered, which attempt to support the claim that physicians have an obligation to treat, fail. It is suggested, rather, that common humanity, which physicians share with those who suffer from AIDS, ought to be the basis for engaging in the care of AIDS patients.  相似文献   
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This investigation focused on the interrelationships among students' study activities, students' self-concept of academic ability ratings, students' academic achievement, and instructional practices in 12 high school biology courses. Using a framework derived from a previous investigation, course features were classified into those that appear to (a) place demands on, (b) support, or (c) compensate for student engagement in particular study activities. Students' study activities, self-concept of academic ability ratings, and achievement were measured with experimenter-developed instruments. Results are reported for (a) characteristics of instruments and course features, (b) relationships between central factors of the investigation, and (c) multi-level relationships between course features and student variables. Results at the student level indicated that self-concept of academic ability and, to a lesser extent, students' study activities were positively associated with student achievement. Students' self-concept of academic ability ratings were also linked to students' engagement in generative, proactive study activities. At the course level the supportive practices of providing challenging homework assignments and extensive feedback on student coursework were associated with student engagement in effortful, generative, proactive study activities. The provision of extensive feedback was also associated with high student achievement. Multi-level relationships were analysed using hierarchical linear modelling (HLM) analyses. These analyses revealed, for example, that in courses in which little or no feedback is given on homework assignments, the relationship between achievement and student engagement in diligent effort management activities was enhanced. Other HLM analyses were conducted to examine the mediating role of course features on the relationship between students' self-concept of academic ability and their study activities and achievement. For example, the presence of challenging course demands was associated with an enhancement of the relationship between self-concept of academic ability and achievement whereas the presence of instructor provisions (supports and compensations) designed to reduce course demands was associated with a reduction in this relationship.  相似文献   
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