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71.
72.
This paper describes an amplifier for an electroencephalograph with gain of 1×104 to 1×106 and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit.  相似文献   
73.
A unique relationship exists between physicians and philosophers — one that expands on the constructive potential of the liaison between physicians and, for example, theologians, on the one hand, or, social workers on the other. This liaison should focus in the scientific aspects of medicine, not just the ethical aspects. Philosophers can provide physicians with a perspective on both the philosophy and the history of medicine through the ages — a sense of how medicine has adapted to the social cultural and ethical needs of each period. This perspective, while emphasizing medicine asscience, should not be limited to matters of methodology, or to criteria for distinguishing science from other intellectual pursuits, but should be concerned also with the history, sociology and politics of science. Both physicians and philosophers stand to gain from a strengthening of their active liaison now as never before; but most of all, the public will be the beneficiary.  相似文献   
74.
Fear of Success (FOS) was originally conceived as a unidimensional motive. However, there is both theoretical and empirical support for the hypothesis that FOS is multidimensional. We factor analyzed the responses of 236 undergraduates to twenty-oneConcern Over the Negative Consequences of Success items and found four factors. Our four factors show considerable overlap with dimensions based on theoretical accounts of FOS etiology as well as with the factor structures obtained from two other factor analytic studies. Thus, there is converging evidence that FOS is multidimensional. The relationship between multidimensional FOS and a multidimensional approach to achievement motivation is discussed.  相似文献   
75.
To test Coyne's (1976b) theory of depression, students' levels of depressive symptoms, reassurance seeking, and self-esteem were assessed at Time 1, and their same-gender roommates' appraisals of them were assessed 5 weeks later. Mildly depressed students engaged in the type of reassurance seeking described by Coyne. Among men, but not women, mildly depressed students were rejected if they strongly sought reassurance and had low self-esteem but not if they did not seek reassurance or had high self-esteem. Although induction of depressed symptoms in roommates did occur, this contagion effect did not account for the depression-rejection relationship. The prediction that unsupportive, intolerant, or unempathic others would be particularly likely to respond with rejection to reassurance-seeking depressed students with low self-esteem received partial support. Implications for future work on the interpersonal aspects of depression are discussed.  相似文献   
76.
A consecutive sample of mid- and late-life bereaved spouses were randomly assigned to treatment and no-treatment groups. Two hypotheses were tested: (1) that brief group psychotherapy during the early stages of loss would facilitate adjustment assessed by measures of mental health, positive psychological states, social role, and mourning; and (2) that positive effects would be maximized for subjects who were more distressed psychologically. Although group participants, compared with untreated controls, did over 1 year show modest improvement on role functioning and positive psychological states, overall the study failed to find substantial support for the two major hypotheses. Both experimental and control groups showed improvement over the year, particularly on measures of mental health and mourning. Differential benefit was not observed for the high-risk group.  相似文献   
77.
This article examines and clarifies controversies about the concept of illness in the field of family therapy. We contend that illness, as traditionally understood in all cultures, is a relational, transactional concept that is highly congruent with core principles of present-day family theories. Family therapists need not buy into a biotechnical, reductionistic reframing of illness as disease. Rather, it is more appropriate to conceptualize and work with illness as a narrative placed in a biopsychosocial context. Such a narrative includes how shared responsibility for coping and for finding solutions can take place, without becoming involved in disputes about causal models.  相似文献   
78.
A previous study (Leung, Bond, & Schwartz, 1990) established that an expectancy-valence model could be used effectively to explain behaviours in three social domains both within and across cultures. In this study the model was applied to the domains of resource allocation and conflict resolution in order to pinpoint which expectancies and which valences were carrying the explanatory weight of the respondents' behavioural strategies. For both Israeli and Hong Kong students the expectancies and, less strongly, the valences tapping harmony and performance quality were important for resource allocation; those tapping animosity reduction and process control, for conflict resolution. Suggestions were offered for broadening the net of explanatory constructs for future work aimed at specifying subjective factors associated with justice-related behaviours.  相似文献   
79.
Effects of persuasive messages, responsibility denial (RD), and attitude-accessing on blood-giving attitudes, intentions, moral obligations, and behavior were examined. In Study 1, participants (n= 84) who heard a message emphasizing moral reasons for donating indicated a more favorable postmessage attitude and stronger moral obligation to donate than participants exposed to a message aimed at reducing fear, a combined moral and fear- reduction message, or no message. Combined message participants showed greatest intent to donate, yet only 14% of all participants attended a campus drive. In Study 2, low (n= 52) and high (n= 60) RD individuals heard the message arguments and were asked to access their attitudes. Low compared to high RD individuals stated a stronger sense of moral obligation, particularly when they accessed their thoughts relevant to blood donating, and behavioral intention, especially in the combined message condition. Few participants attended a blood drive (12.5%), yet most were low RD individuals from the nonaccessed attitude condition (83%). Results suggest that few individuals will engage in the altruistic act of blood donating, despite the experimental use of persuasive messages and accessing issue-relevant attitudes.  相似文献   
80.
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