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21.
This paper gives a method for determining a sample size that will achieve a prespecified bound on confidence interval width for the interrater agreement measure,. The same results can be used when a prespecified power is desired for testing hypotheses about the value of kappa. An example from the literature is used to illustrate the methods proposed here.  相似文献   
22.
We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.  相似文献   
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Fighting pairs of isolated DBA/2 mice showed a significant increase in tail-flick response latencies independent of whether opponents were losing or winning the combat. The effect lasted less than 10 min in both animals. Elevated pain thresholds were also found in isolates that attacked a nonaggressive conspecific, and were prevented by naltrexone (0.2 mg/kg), while a larger dose (1.0 mg/kg) inhibited the attack behavior. A small increase in pain threshold was observed after exposure of isolates to the test box alone, while isolation per se had no effect on baseline tail-flick latencies. The data demonstrate that endogenous pain suppressing systems are activated during attack and suggest that this opioid-mediated antinociception is a correlate of the isolation syndrome, reflecting enhanced arousal of the attacking animal.  相似文献   
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Previous research on the effect of lecture handouts on student learning indicates that students who are given skeletal handouts usually perform better in course examinations than students who take all their own notes. The present study investigates whether the amount of detail in the handout is a critical factor in this. A randomized groups experiment was conducted in the context of a course on dental surgery. Four lecture handout conditions (headings and full text; headings and key points; headings only; no supplementary materials) were compared on tests 2 days and 2 weeks after the lecture. The significant differences between conditions were: ‘headings only’ better than ‘headings and key points’ on the first test; ‘headings only’ better than ‘no supplementary materials’ on the second test; and ‘headings and full text’ better than ‘no supplementary materials’ on the second test. These results indicate that the amount of detail is a critical factor in handout effectiveness.  相似文献   
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Braun, A.L., & Novak, D.E. (1986, November/December). A study of EAP non-utilization. EAP Digest, pp. 52–55. O'Connell, V. (1987, March/April). A strategy for overcoming supervisors' resistance. EAP Digest, pp. 63–66. Penzer, W.N. (1987, March/April). Toward sustaining quality mental health services. EAP Digest, pp. 35–40.  相似文献   
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This article presents a simulation-based tutorial system for exploring parallel distributed processing (PDP) models of information processing. The system consists of software and an accompanying handbook. The intent of the package is to make the ideas underlying PDP accessible and to disseminate some of the main simulation programs that we have developed. This article presents excerpts from the handbook that describe the approach taken, the organization of the handbook, and the software that comes with it. An example is given that illustrates the approach we have taken to teaching PDP, which involves presentation of relevant mathematical background, together with tutorial exercises that make use of the simulation programs.  相似文献   
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This paper examines the reactions of physicians and other health-professionals when they become involved in decisions about the death of their patients. The way people understand the condition of death has a profound influence on attitudes towards death and dying issues. Four traditional views of death are explored. The problem that physicians have in helping patients die (be it by hastening death through pain control, assisting patients in suicide or by more active means) is analyzed. Physicians, in dealing with such patients, must be mindful of their own, and their patients beliefs as well as mindful of the community in which such dying takes place. They must try to reconcile these often divergent views but can neither paternalistically deny patients their rational will, hide themselves behind an appeal to the law or go against their own deeply held moral views. When such views cannot be reconciled, compassionate transfer to a more compatible physician may be necessary.  相似文献   
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