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241.
Self-sacrificing behavior of the leader and the extent to which the leader is representative of the group (i.e., group prototypical) are proposed to interact to influence leadership effectiveness. The authors expected self-sacrificing leaders to be considered more effective and to be able to push subordinates to a higher performance level than non-self-sacrificing leaders, and these effects were expected to be more pronounced for less prototypical leaders than for more prototypical leaders. The results of a laboratory experiment showed that, as expected, productivity levels, effectiveness ratings, and perceived leader group-orientedness and charisma were positively affected by leader self-sacrifice, especially when leader prototypicality was low. The main results were replicated in a scenario experiment and 2 surveys.  相似文献   
242.
Existing transformational leadership research has focused primarily on the behaviors of leaders and their effects on followers. The authors extended this research by examining the social networks of managers who exhibit transformational leadership behaviors. Their focus was on the network of relationships that managers develop and whether they hold key positions in the organization's informal social networks. In a field study using data from 39 managers and 130 nonmanagement employees of 6 organizations, the authors found that managers who score higher on transformational leadership tend to hold more central positions in organizational advice and influence networks. Furthermore, the direct reports of these leaders were also more central in informal organizational networks. These results illuminate one of the ways that managers who exhibit transformational leadership behaviors may exert influence in organizations.  相似文献   
243.
The authors of this essay suggest that the field of bioethics and Christian theology have a great deal to offer to each other. The authors first argue that representatives from both fields must first make sure that they fully and correctly represent their respective position. In other words, scientists, ethicists, and theologians alike must make sure that they present their fields and not use their knowledge merely for personal gain at the stake of misguiding people. Once this is established, the authors then proceed to show the intimate relationship between Christianity and medicine that has existed throughout the ages. It is a call for a continuation of such a relationship that the authors suggest between bioethics and theology. Through an integration of bioethics and Christian theology, both scientists/physicians and theologians are able to gain greater insight into the human person—a focus in both fields.  相似文献   
244.
Objectives: To understand the impact of physicians and patients religious/spiritual orientation on discussions of spiritual issues. Methods: We performed semi-structured interviews of 10 Missouri family physicians and 10 patients of these physicians, selecting subjects nonrandomly to represent a range of demographic factors, practice types, and chronic or terminal illness. We coded and evaluated transcribed interviews for themes. Results: Respondents expressed that similar belief systems facilitate patient–physician spiritual interactions and bring confidence to their relationships. Those holding dissimilar faiths noted limited ability to address spiritual questions directly. They cited significant barriers to spiritual interaction but considered that ecumenism, use of patient-centered care, and negotiation skills lessen these barriers. Conclusions: Our respondents view spirituality similarly to other aspects of the physician–patient relationship involving differing viewpoints. Where discordance exists, cross-cultural, patient-centered, diplomatic approaches facilitate spiritual discussions.  相似文献   
245.
Luminance edges seem to have an important role in visual feature binding and, more specifically, in visual completion because luminance differences are important for the perception of depth. We investigated this claim in two experiments in which the primed-matching paradigm was used. In Experiment 1, we investigated conditions under which either a partly occluded shape or an occluder was isoluminant with respect to the background. In Experiment 2, the partly occluded shape and the occluder were isoluminant with respect to each other. Evidence was found for visual completion in all cases, and we therefore conclude that luminance edges are not essential for visual completion.  相似文献   
246.
Despite the widespread belief that the subjective speed of the passage of time increases with age, empirical results are controversial. In this study, a combination of questionnaires was employed to assess subjective time perception by 499 subjects, ages 14 to 94 years. Pearson correlations and nonlinear regression analyses on a variety of questionnaires and the age of the participants show that the momentary perception of the passage of time and the retrospective judgment of past periods of time are a function of chronological age; however, small-to-moderate effects accounted for at most 10% of the variance. Results generally support the widespread perception that the passage of time speeds up with age. These results are discussed in the context of models of prospective and retrospective time judgment, but interpretations have to be treated with caution given methodological limitations.  相似文献   
247.
The goal of the study was to establish whether false allegations of sexual offences with an unknown perpetrator can be distinguished from accurate allegations. Case files of 27 true allegations of sexual offences with an unknown perpetrator were compared to those of 14 false allegations. The comparison was guided by a list of 43 criteria that are hypothesized to differentiate between true and false allegations of sexual assault. Analyses indicated the employed criteria differentiated true from false allegations to a certain extent. However, the discriminative strength of some criteria appeared to be stronger than that of others. Research is required to assess further the discriminative power of these criteria.  相似文献   
248.
In Experiment 1, the effects of stop signal modality on the speed and efficiency of the inhibition process were examined. Stop signal reaction time (SSRT) and inhibition function slope in an auditory stop signal condition were compared to SSRT and inhibition function slope in a visual stop signal condition. It was found that auditory stop signals compared to visual stop signals enhanced both the speed and efficiency of stopping. The modality effects were attributed to differences in the neurophysiological processes underlying perception. However, Experiment 2 demonstrated that the modality difference was larger for 80 dB(A) auditory stop signals than 60 dB(A) auditory stop signals. This effect was reconciled with the suggestion that loud tones are more capable of eliciting immediate arousing effects on motor processes than weak tones and visual stimuli. The second purpose of the present investigation was to explore the utility (and potential advantages) of an alternative way of setting stop signal delay relative to mean reaction time (MRT). The method that was suggested compensates for inter-individual differences in primary task reaction speed by setting stop signal delays as proportions of the subjects' MRT.  相似文献   
249.
Developmental trajectories of peer-nominated aggression, risk factors at baseline, and outcomes were studied. Peer nominations of aggression were obtained annually from grades 1 to 3. Three developmental trajectories were identified: an early-onset/increasers trajectory with high levels of peer-nominated aggression at elementary school entry and increasing levels throughout follow-up; a moderate-persistent trajectory of aggression in which children were characterized by moderate levels of physical aggression at baseline; and a third trajectory with stable low levels of aggression. Children following the early-onset/increasers trajectory showed physical forms of aggression at baseline. Male gender and comorbid attention deficit/hyperactivity problems, oppositional defiant problems and poor prosocial behavior plus negative life events predicted which children would follow the early-onset/increasers trajectory of aggression. The outcomes associated with the early-onset/increaser children suggest high risk for chronically high levels of aggressive behavior.  相似文献   
250.
Delayed attentional engagement in the attentional blink   总被引:6,自引:0,他引:6  
Observers often miss the 2nd of 2 visual targets (first target [T1] and second target [T2]) when these targets are presented closely in time; the attentional blink (AB). The authors hypothesized that the AB occurs because the attentional response to T2 is delayed by T1 processing, causing T2 to lose a competition for attention to the item that follows it. The authors investigated this hypothesis by determining whether the AB is attenuated when T2 is precued. The results from 4 experiments showed that the duration and magnitude of the AB were substantially reduced when T2 was precued. The observed improvement in T2 report did not occur at the expense of T1 report, suggesting that processing of T1 was already completed or was at least protected when the cue was presented. The authors conclude that, during the AB, there is a delay between detection and the selection of target candidates for consolidation in short-term memory.  相似文献   
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