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221.
The esophageal obturator airway (EOA) is a device used throughout the United States to facilitate artificial respiration of critically ill patients who are not hospitalized. Its use is restricted to persons who are over 15 years old because obturators for children are not available. A protocol submitted to an institutional review board (IRB) intended to develop EOAs suitable for use in children. The investigators proposed to perform preliminary testing of these devices on children who had sustained irreversible loss of brain function (“brain death”). In its review of this protocol, the IRB had to confront several vexing questions.  相似文献   
222.
Various arguments have been given against positive euthanasia, but little attention has been given to the question of whether these arguments are uniformly effective in all contexts. There appears to be a range of cases, involving non-voluntary killing of irreversibly unconscious patients, in which these arguments do not succeed. Various reasons have been given in support of positive killing in such cases. It can be argued that there is a range of cases for which a policy of allowing positive killing is morally required. However, currently there are legal obstacles to implementing such a policy.  相似文献   
223.
We examined the relationship between potential family vulnerability factors (stressor and strains), manifestations of maladaptation (family discord and distress), family strengths (hardiness), and measures of bonadaptation (quality of life) as reported by 188 men and women representing 100 Idaho farm and ranch families. Family strains, and stressors unique to farming and ranching, were positively associated with family discord and distress but negatively associated with hardiness and quality of life. Greater family hardiness as reported by both wives and husbands was positively correlated with their perceptions of family quality of life. The results have implications for mental health professionals and family life educators whose goal is to help farm and ranch families manage stress more effectively, increase hardiness, and enhance their overall quality of life.  相似文献   
224.
Differences among full-time (n=1066), part-time (n=132), and moonlighting employees (n=153) in a variety of occupations were examined. Moonlighters as compared to full-timers were younger, more frequently male, perceived less educational fit with their main jobs, and were primary wage earners. Full-timers as compared to part-timers were more frequently male, married, and primary wage earners. Part-timers had the greatest turnover, but no differences were detected for other withdrawal behaviors. Part-timers were more satisified with working conditions but were less satisfied with extrinsic rewards and life in general. Moonlighters expressed a stronger work ethic and placed less importance on working conditions.A version of this paper was presented at the 1991 Meetings of the Southwest Division of the Academy of Management in Houston, TX.  相似文献   
225.
226.
Sixteen right-handed participants without formal musical training performed a rhythmic multifrequency coordination task for several hours over a one-week period. Two groups were studied with respect to the assignment of hand to frequency: 1L:2R, in which the preferred right hand performed the higher frequency, and 2L:1R in which the non-preferred left hand performed the higher frequency. Performance asymmetries in terms of relative phase stability were initially expected and confirmed. The 1L:2R pattern was more stable than 2L:1R. It has been suggested that performance asymmetries result from asymmetrical coupling between the limbs as influenced by handedness. This study examined whether the acquisition of 2L:1R, the less stable of the two patterns, required the formation of asymmetrical coupling such that the faster hand would exert a greater forcing on the slower hand than vice versa, a supposition put forth in many studies of bimanual polyrhythmic tapping. The present data provide quantitative evidence that, in terms of stability (as quantified by relative phase uniformity, transition pathways, and lead-lag relations), handedness asymmetries, as well as acquired asymmetries, can be captured by low-dimensional dynamics consisting of symmetric and asymmetric coupling terms. Received: 18 November 1996 / Accepted: 6 May 1997  相似文献   
227.
Repetition priming is defined as a gain in item recognition after previous exposure. Repetition priming of face recognition has been shown to last for several months, despite contamination by everyday exposure to both experimental and control faces in the interval. Here we show that gains in face recognition in the laboratory are found from faces initially seen in a rather different context— on subject recruitment posters, even when the advertisements make no specific mention of experiments involving face recognition. The priming was greatest when identical pictures were shown in the posters and in the test phase, although different views of faces did give significant priming in one study. Follow-up studies revealed poor explicit memory for the faces shown on the posters. The results of these experiments are used to develop a model in which repetition priming reflects the process of updating representations of familiar faces.  相似文献   
228.
Summary Two experiments are reported in which we examined the hypothesis that the advantage of the right hand in target aiming arises from differences in impulse variability. Subjects made aiming movements with the left and right hands. The force requirements of the movements were manipulated through the addition of mass to the limb (Experiments 1 and 2) and through control of movement amplitude (Experiment 1). Although the addition of mass diminished performance (i. e., it increased movement times in Experiment 1 and increased error in Experiment 2), the two hands were not differently affected by the manipulation of required force. In spite of the fact that the right hand exhibited enhanced performance (i. e., lower movement times in Experiment 1 and greater accuracy in Experiment 2), these advantages were not reflected in kinematic measures of impulse variability.We are grateful to an anonymous reviewer for clarification of this distinction.  相似文献   
229.
The recognition and classification of category members was explored, following a variable number of learning trials. In Experiment 1, subjects received 1 or 9 learning trials, followed by a recognition-then-classification test containing old, new, prototype, and foil patterns. In Experiment 2, subjects received 1, 6, or 12 trials, and made either classification or recognition judgments. In each experiment, classification accuracy for all item types was at near-chance -performance after a single trial but steadily increased with increased learning trials. On the transfer test, oldness judgments were highest for the category prototype after a single trial. However, with increased learning trials, oldness judgments increased for old instances and decreased for the category prototype and new instances. We suggest that false recognition of the category prototype, especially after a single learning trial, need not reflect an abstraction process. We discuss the possibility that an abstracted prototype may emerge with additional learning as an unfamiliar, ideal point.  相似文献   
230.
It is argued that the format for developing recent versions of the Diagnostic and Statistical Manual of Mental Disorders (DSM) taxonomy is constrained in ways that seriously impair the quality of the product. These constraints include inappropriate assumption of a categorical model, ensured persistence of traditional categories of disorder, excessive concern with interdiagnostician agreement, insufficient attention to the issue of construct validity, and excessive preoccupation with clinician acceptance. These problems and certain others are illustrated with an analysis of the nosologic status of the schizophrenia construct. There is a significant danger that the adequacy of DSM-IV will be compromised by continuing difficulties of this sort.  相似文献   
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