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81.
This essay will address the ethical issues that have emerged in the first considerations of the newly emerging stem cell technology. Many of us in the field of bioethics were deliberating related issues as we first learned of the new science and confronted the ethical issues it raised. In this essay, I will draw on the work of colleagues who were asked to reflect on early stages of the research (members of the IRBs, the Geron Ethicist Advisory Board, and the National Bioethics Advisory Commission) as the field debated the issues of consent, moral status, use of animal tissues, abortion, use of fetal tissue, and the nature and goals of entrepreneurial research. In this new capacity, ethicists weighed the problem of privacy, the role of justice considerations, and the issues of the marketplace in science. At this point, it is clear that far more issues remain unresolved than are settled, that there is largely unexplored territory ahead, and that the single most important task that faces us as a field is a steady call for ongoing conversation and public debate.  相似文献   
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Although dependence in effect sizes is ubiquitous, commonly used meta-analytic methods assume independent effect sizes. We describe and illustrate three-level extensions of a mixed effects meta-analytic model that accounts for various sources of dependence within and across studies, because multilevel extensions of meta-analytic models still are not well known. We also present a three-level model for the common case where, within studies, multiple effect sizes are calculated using the same sample. Whereas this approach is relatively simple and does not require imputing values for the unknown sampling covariances, it has hardly been used, and its performance has not been empirically investigated. Therefore, we set up a simulation study, showing that also in this situation, a three-level approach yields valid results: Estimates of the treatment effects and the corresponding standard errors are unbiased.  相似文献   
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Abstract

Work meaning patterns combine dimensions such as work centrality, expressive versus economic work goals, and entitlement versus obligation societal norms into a holistic picture of the evolution over time of the meaning of work. Data from a longitudinal study in eight countries are used to establish major work meaning patterns and to study their stability during early career paths. Further, some potential determinants of these work meaning patterns are analysed and their consequences for later careers are considered. Statistical analyses include: cluster analysis, multiple discriminant analysis, analysis of covariance combined with multiple classification analysis, analysis of variance, and chi-square analysis. Five cross-national work meaning patterns are identified for machine operators in their third year in the labour market. One-third of the sample had remained in the same work meaning pattern for 2 years, while two-thirds had changed their work pattern. Respondents' age, country, prior work environment, and prior work socialization behaviours and outcomes have an impact on work meanings held 2 years later. In addition the respondent's work meaning pattern allows subsequent career enhancing strategies and effort expenditure at the job to be predicted.  相似文献   
84.
The present study focuses on the effect of selective attention on causal learning. Three effects of the level of attention to predictive symptoms in positive and negative contingency learning tasks are reported. First, participants accurately detected a positive relationship between an incidental cue and a contingent outcome, although judgements were slightly lower than those for the attended cue. Second, participants were unable to detect negative relationships between incidental cues and outcomes, which suggests a major role of selective attention in this type of learning. Third, participants retrieved the frequency of each trial type more accurately in the attended conditions than in the incidental conditions. These findings show how attention guides and constrains human causal learning and reveal an inattentional blindness effect for negative contingency learning.  相似文献   
85.
Subjective Situations and Logical Omniscience   总被引:1,自引:0,他引:1  
Moreno  Antonio  Cortés  Ulises  Sales  Ton 《Studia Logica》2002,72(1):7-29
The beliefs of the agents in a multi-agent system have been formally modelled in the last decades using doxastic logics. The possible worlds model and its associated Kripke semantics provide an intuitive semantics for these logics, but they commit us to model agents that are logically omniscient. We propose a way of avoiding this problem, using a new kind of entities called subjective situations. We define a new doxastic logic based on these entities and we show how the belief operators have some desirable properties, while avoiding logical omniscience. A comparison with two well-known proposals (Levesque's logic of explicit and implicit beliefs and Thijsse's hybrid sieve systems) is also provided.  相似文献   
86.
Chrono‐epidemiology is the study of the distribution of health events according to time. The time intervals taken into account have cyclic patterns and include circadian, weekly, seasonal, and circannual rhythms. In the behavioural field, chrono‐epidemiology can be and has been applied to studies concerning the causes of death (suicide and homicide), clinical events such as admissions to and contacts with mental healthcare services, and the seasonal distribution of crime involving the use of violence. Frequently reported findings include clear circadian and seasonal rhythms present in the phenomenon of suicide (rhythms more evident in the case of violent suicide); seasonal rhythms in the expression of aggression by patients hospitalised for mental illness; and a circannual recurrence of crimes with a violent component. The intrinsic circadian and seasonal rhythms of some neuronal systems, particularly those of serotonin, involved in the control of mood and impulses, are thought to favour the behavioural rhythms observed, although the contribution of socio‐environmental factors, such as the fluctuation of supportive networks according to time, is also acknowledged. By demonstrating non‐casual recurrence of certain behaviour and by exploring the socio‐biological basis of the rhythms beneath these recurrences, chrono‐epidemiology may offer important etiologic and preventive clues to the understanding of the biological and environmental correlates of aggressive behaviour. Aggr. Behav. 28:477–490, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
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The present research investigated the notion of fit between supervisors’ power tactics and subordinates’ need for cognitive closure (NFCC) on subordinates’ burnout and stress. Subordinates who tend to avoid ambiguity (high NFCC) were expected to experience relatively less burnout (Study 1) and stress (Study 2) if their supervisors utilize harsh (controlling and unequivocal) power tactics and more burnout and stress if their supervisors utilize soft (autonomy-supportive and equivocal) power tactics. In contrast, it was expected that subordinates who avoid firm and binding conclusions (low NFCC) would experience relatively less burnout and stress if their supervisors use soft power tactics and more burnout and stress if they use harsh power tactics. Two studies conducted in diverse organizational settings supported these hypotheses. Collectively, these results support the conclusion that soft (vs. harsh) power tactics are not always associated with better (vs. worse) organizational outcomes. Theoretical and practical implications for organizations are discussed.  相似文献   
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