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101.
After reviewing portions of the 21st Century Nanotechnology Research and Development Act that call for examination of societal and ethical issues, this essay seeks to understand how nanoethics can play a role in nanotechnology development. What can and should nanoethics aim to achieve? The focus of the essay is on the challenges of examining ethical issues with regard to a technology that is still emerging, still ‘in the making.’ The literature of science and technology studies (STS) is used to understand the nanotechnology endeavor in a way that makes room for influence by nanoethics. The analysis emphasizes: the contingency of technology and the many actors involved in its development; a conception of technology as sociotechnical systems; and, the values infused (in a variety of ways) in technology. Nanoethicists can be among the many actors who shape the meaning and materiality of an emerging technology. Nevertheless, there are dangers that nanoethicists should try to avoid. The possibility of being co-opted from working along side nanotechnology engineers and scientists is one danger that is inseparable from trying to influence. Related but somewhat different is the danger of not asking about the worthiness of the nanotechnology enterprise as a social investment in the future.  相似文献   
102.
Johnson DN 《Memory & cognition》2000,28(8):1303-1309
The effects of task demands on the representation of letter strings in long-term repetition priming (LTRP) were explored in two lexical decision experiments. The stimuli in both experiments were words and nonwords, some presented horizontally and some vertically. The only difference between the two experiments was the response required by the participant. In Experiment 1, the participants pressed one of two buttons, indicating whether or not a given stimulus was a word. In Experiment 2, the participants pressed one of four buttons, indicating both the lexical status and the orientation of a given stimulus. The results were that in Experiment 1, LTRP was not disrupted by a change in stimulus orientation, whereas in Experiment 2 it was, suggesting that the nature of the stimulus representation utilized in LTRP is partially dependent on the demands of the task.  相似文献   
103.
A common way of studying developmental disorders is to adopt a static neuropsychological deficit approach, in which the brain is characterized in terms of a normal brain with some parts or ‘modules’ impaired. In this paper we outline a neuroconstructivist approach in which developmental disorders are viewed as alternative developmental trajectories in the emergence of representations within neural networks. As a concrete instantiation of the assumptions underlying this general approach, we present a number of simulations in an artificial neural network model. The representations that emerge under different architectural, input and developmental timing conditions are then analysed within a multi‐dimensional state space. We explore alternative developmental trajectories in these simulations, demonstrating how initial differences in the same parameter can lead to very different outcomes, and conversely how different starting states can sometimes result in similar end states (phenotypes). We conclude that the assumptions of the neuroconstructivist approach are likely to be more appropriate for analysing developmental deviations in complex dynamic neural networks, such as the human brain.  相似文献   
104.
This paper offers new insights into the behavioural origins of the ‘favourite–longshot’ bias — an established feature of betting markets, whereby longshots win less often than the subjective probabilities imply and favourites more often. A number of alternative explanations has been offered for this phenomenon but the main debate focuses on whether it is caused by the behaviour of those supplying betting markets (bookmakers) or of the demand‐side agents in these markets (bettors) . This study analyses a new data source which offers detailed information for a large sample of recent UK horseraces on decision‐making behaviour within the parimutuel and the parallel bookmaker‐based betting markets. The results offer strong evidence for the existence of the ‘favourite–longshot’ bias in bookmaker‐based markets, with a corresponding absence of such an effect in the parimutuel case. These results offer support for the view that the origins of the ‘favourite–longshot’ bias lie principally in the decisions of bookmakers rather than in the decisions of bettors. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
105.
106.
Research on the hopelessness and self-esteem theories of depression (Abramson, Metalsky, & Alloy, 1989; Metalsky, Joiner, Hardin, & Abramson, 1993) suggests that HIV-infected persons with depressotypic attributional style (AS) and low self-esteem (SE) may be at risk for onset of a syndrome referred to as hopelessness depression (HD). In a prospective study conducted to test these theories, measures of anxiety and depression, AS, and SE were administered to 85 HIV+ and 43 HIV– men; symptoms were reassessed 6 months later. Results indicated that: (1) The interaction of AS, SE, and HIV status predicted change in HD symptoms, but not overall depression or anxiety symptoms; (2) HIV+ men with depressotypic AS and high SE had increased HD symptom levels while other men with high SE had decreased HD symptom levels; (3) HD symptoms remained stable over the 6-month interval among men with low SE; and (4) High SE predicted decreases in anxiety symptoms among HIV– men, but not among HIV+ men. Contrary to the study hypothesis, these findings suggest that among individuals with life-threatening illnesses such as HIV infection, those with depressotypic AS and high SE may be at highest risk for onset of HD.  相似文献   
107.
In Study 1, the effect of making tokens contingent on correct performance of low social position preschoolers on the McCarthy Scales of Children's Abilitieswas examined. Preschoolers in a token reinforcement group scored significantly higher (mean=8 IQ points) than subjects in a control group. In Study 2, the effect of tokens on McCarthyresults was examined as a function of social position in a 2×2 design. The high social position control group scored significantly above the low social position control. The low social position token reinforcement group, however, performed as well as both the high social position control and token reinforcement groups. Use of systematic reinforcement contingencies to reduce test error is discussed.  相似文献   
108.
109.
In Britain today, counsellors and therapists often work with people from a diverse range of ethnic groups whose cultures are substantially different from their own. There is increasing concern that people from black and ethnic communities have limited access to appropriate services—despite service planners' and providers' statements that mental health services are being restructured to become more sensitive, relevant and meaningful to these communities. This paper is an attempt to redress the balance with an emphasis on the therapeutic needs of South Asian communities. It aims to challenge assumptions and beliefs held by therapists and counsellors, question therapeutic practice based within a white, middle-class ideology, raise awareness of an 'Asian' perspective in therapy, and provide some guidelines for good practice in transcultural counselling.  相似文献   
110.
The Attitudes Toward Religion Scale (ATRS) was developed to access the level of interest in and position toward the five state-approved religions in China. Data were analysed across two samples of Chinese college students. With Sample 1 (= 278), exploratory factor analyses were used to select the 10 ATRS items corresponding to two factors: Interest and Position. With Sample 2, confirmatory factor analyses (= 270) cross-validated the two-factor oblique model as well as a bifactor model. Cronbach alphas of ATRS subscale scores in the two samples ranged from .75 to .85. ATRS-Interest and Position were both positively associated with number of close relationships with religious people. In addition, negative attitudes toward religion was associated with being religiously proselytised by strangers. Moreover, female students reported more favourable attitudes toward religion compared to their male counterparts. The overall results support ATRS as a psychometrically strong and promising measure.  相似文献   
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